01 03 traffic statistic items

M900/M1800 Base Station Controller Traffic Statistic Manual - Volume I Contents

Issue 02 (2008-10-07) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd i

Contents

3 Traffic Statistic Items ................................................................................................................3-1 3.1 BSC Measurement Function .........................................................................................................................3-3

3.1.1 General.................................................................................................................................................3-3 3.1.2 Access Measurement Function(1) ........................................................................................................3-4 3.1.3 Access Measurement Function(2) ......................................................................................................3-39 3.1.4 Handover Measurement Function(1) .................................................................................................3-41 3.1.5 Handover Measurement Function(2) .................................................................................................3-75

3.2 SCCP Measurement Function .....................................................................................................................3-94 3.2.1 General...............................................................................................................................................3-94 3.2.2 Statistic Items.....................................................................................................................................3-95

3.3 A-Interface Operation and Management Statistic......................................................................................3-101 3.3.1 General.............................................................................................................................................3-101 3.3.2 Statistic Items...................................................................................................................................3-102

3.4 A-interface Equipment Maintenance Statistic ...........................................................................................3-105 3.4.1 General.............................................................................................................................................3-105 3.4.2 Statistic Items...................................................................................................................................3-105

3.5 A-interface Trunk Board Message Statistic ...............................................................................................3-107 3.5.1 General.............................................................................................................................................3-107 3.5.2 Statistic Items...................................................................................................................................3-108

3.6 CPU Measurement Function .....................................................................................................................3-109 3.6.1 General.............................................................................................................................................3-109 3.6.2 Statistic Items...................................................................................................................................3-110

3.7 BSC Cell Broadcast Measurement ............................................................................................................ 3-111 3.7.1 General............................................................................................................................................. 3-111 3.7.2 BSC Cell Broadcast Measurement Function (Total) ........................................................................ 3-111 3.7.3 BSC Cell Broadcast Measurement Function (Period)......................................................................3-124 3.7.4 BSC Cell Broadcast Measurement Function (Others) .....................................................................3-125

3.8 MTP Measurement Function.....................................................................................................................3-126 3.8.1 General.............................................................................................................................................3-126 3.8.2 Statistic Items...................................................................................................................................3-127

M900/M1800 Base Station Controller Traffic Statistic Manual - Volume I Figures

Issue 02 (2008-10-07) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd iii

Figures

Figure 3-1 CM SERVICE REQUEST rejection process ....................................................................................3-7

Figure 3-2 Circuit paging process ......................................................................................................................3-9

Figure 3-3 CCCH overload process..................................................................................................................3-11

Figure 3-4 Packet paging process.....................................................................................................................3-12

Figure 3-5 immediate assignment transmission process...................................................................................3-12

Figure 3-6 Packet immediate channel assignment procedure...........................................................................3-13

Figure 3-7 CC connection establishment process.............................................................................................3-14

Figure 3-8 Immediate assignment procedure-channel seizure procedure.........................................................3-17

Figure 3-9 Assignment procedure-channel seizure procedure..........................................................................3-17

Figure 3-10 Intra-BSC handover channel seizure procedure............................................................................3-18

Figure 3-11 Incoming BSC handover channel seizure procedure ....................................................................3-18

Figure 3-12 TCH drop for assignment .............................................................................................................3-21

Figure 3-13 Drop for Intra BSC handover........................................................................................................3-21

Figure 3-14 Incoming BSC TCH handover procedure.....................................................................................3-22

Figure 3-15 Successful TCH seizures for very early assignment procedure ....................................................3-22

Figure 3-16 TCH drop for very early assignment.............................................................................................3-24

Figure 3-17 Immediate assignment procedure-channel seizure procedure.......................................................3-25



Figure 3-20 Assignment implementation process.............................................................................................3-28

Figure 3-21 Signaling channel request procedure ............................................................................................3-34

Figure 3-22 Intracell TCHF-TCHH handover success times ...........................................................................3-44

Figure 3-23 internal intercell handover ............................................................................................................3-45

Figure 3-24 Successful internal intercell handover (DIRECTED RETRY) .....................................................3-47

Figure 3-25 Successful Internal intercell handover (not DIRECTED RETRY)...............................................3-48

Figure 3-26 Intra BSC handover ......................................................................................................................3-50

Figures M900/M1800 Base Station Controller

Traffic Statistic Manual - Volume I

iv Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd Issue 02 (2008-10-07)

Figure 3-27 Successful incoming BSC handover.............................................................................................3-51

Figure 3-28 Unsuccessful incoming BSC handover.........................................................................................3-57

Figure 3-29 Incoming BSC handover...............................................................................................................3-61

Figure 3-30 Attempted outgoing BSC handover ..............................................................................................3-62

Figure 3-31 Successful outgoing BSC handover..............................................................................................3-65

Figure 3-32 Unsuccessful outgoing BSC handovers ........................................................................................3-68


Figure 3-34 Unsuccessful BSC internal handovers ..........................................................................................3-70


Figure 3-36 Outgoing system HO attempts ......................................................................................................3-92

Figure 3-37 Unsuccessful outgoing system HOs..............................................................................................3-93

Figure 3-38 Establishment of SCCP signaling connection (successful)...........................................................3-97

Figure 3-39 Establishment of SCCP signaling connection (failure).................................................................3-98

Figure 3-40 Establishment of SCCP signaling connection and data transmission ...........................................3-99

Figure 3-41 Transmission of SCCP signaling.................................................................................................3-100

Figure 3-42 Send broadcast short message.....................................................................................................3-113

Figure 3-43 Delete short message ..................................................................................................................3-113

Figure 3-44 Query broadcast channel.............................................................................................................3-114

Figure 3-45 Query the transmission of broadcast short message ...................................................................3-115

Figure 3-46 Set DRX mode............................................................................................................................3-115

Figure 3-47 Reset cells ...................................................................................................................................3-116

Figure 3-48 BTS reports CBCH overflow......................................................................................................3-120

Figure 3-49 Received "write" messages .........................................................................................................3-120

M900/M1800 Base Station Controller Traffic Statistic Manual - Volume I Tables

Issue 02 (2008-10-07) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd v

Tables

Table 3-1 Statistic items in Access measurement function items (1) ..................................................................3-4

Table 3-2 Statistic items in Access measurement function items(2) .................................................................3-39

Table 3-3 Statistic items in Handover measurement function(1) items ............................................................3-41

Table 3-4 Statistic items in Handover measurement function(2) items ............................................................3-76

Table 3-5 Statistic items in SCCP Measurement Function ...............................................................................3-94

Table 3-6 Statistic items in A-interface Operation and Management Statistic................................................3-101

Table 3-7 Statistic items in A-interface Equipment Maintenance Statistic .....................................................3-105

Table 3-8 Statistic items in A-interface Operation and Management Statistic................................................3-107

Table 3-9 Statistic items in CPU Measurement Function ...............................................................................3-110

Table 3-10 Statistic items in BSC Cell Broadcast Measurement Function (Total) ......................................... 3-111

Table 3-11 Statistic items in BSC Cell Broadcast Measurement Function(Period) ........................................3-124

Table 3-12 Statistic items in BSC Cell Broadcast Measurement Function (Others).......................................3-125

Table 3-13 Statistic items in MTP Measurement Function.............................................................................3-126

M900/M1800 Base Station Controller Traffic Statistic Manual - Volume I 3 Traffic Statistic Items

Issue 02 (2008-10-07) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd 3-1

3 Traffic Statistic Items

About This Chapter

The following table lists the contents of this chapter.

Section Describes

3.1 BSC Measurement Function Describes the statistic items of BSC Measurement Function.

3.2 SCCP Measurement Function Describes the statistic items of SCCP Measurement Function.

3.3 A-Interface Operation and Management Statistic

Describes the statistic items of A-Interface Operation and Management Statistic.

3.4 A-interface Equipment Maintenance Statistic

Describes the statistic items of A-Interface Equipment Maintenance Statistic.

3.5 A-interface Trunk Board Message Statistic

Describes the statistic items of A-Interface Trunk Board Message Statistic.

3.6 CPU Measurement Function Describes the statistic items of CPU Measurement Function.

3.7 BSC Cell Broadcast Measurement

Describes the statistic items of BSC Cell Broadcast Measurement Function.

3.8 MTP Measurement Function Describes the statistic items of MTP Measurement Function.

3.9 Cell Measurement Function Describes the statistic items of Cell Measurement Function

3.10 Power Control Measurement Describes the statistic items of Power Control Measurement Function.

3.11 Call Drop Measurement Describes the statistic items of Call Drop Measurement Function.

3 Traffic Statistic Items M900/M1800 Base Station Controller


3-2 Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd Issue 02 (2008-10-07)

Section Describes

3.12 SITE Initial Measurement Function

Describes the statistic items of Site Initial Measurement Function.

3.13 BTS Initial Measurement Function

Describes the statistic items of Cell Initial Measurement Function.

3.14 Cell Broadcast Statistic Describes the statistic items of Cell Broadcast Statistic.

3.15 Outgoing Inter Cell Handover Measurement Function

Describes the statistic items of Outgoing Inter Cell Handover Measurement Function.

3.16 Incoming Inter Cell Handover Measurement Function

Describes the statistic items of Incoming Inter Cell Handover Measurement Function.

3.17 Undefined Adjacent Cell Measurement Function

Describes the statistic items of Undefined Adjacent Cell Measurement Function.

3.18 Defined Adjacent Cell Measurement Function

Describes the statistic items of Defined Adjacent Cell Measurement Function.

3.19 Receiving Quality Measurement

Describes the statistic items of Receiving Quality Measurement Function.

3.20 Receiving Level Measurement Function

Describes the statistic items of Receiving Level Measurement Function.



3.1 BSC Measurement Function 3.1.1 General

The statistic items in BSC Measurement Function are used to measure the traffic volume of all the cells in the BSC.

The BSC Measurement Function includes: Access measurement function, Handover measurement function(1), and Handover measurement function(2).

The statistic items in BSC Measurement Function can be divided into following classifications:

Statistics of times that MSC rejects MS’s service request, including the statistics according to different rejection causes.

The status of circuit service and packet service paging being transmitted and implemented, including the measurement at A (Pb) interface and Abis interface.

Measurement of circuit service and packet service CCCH overload. The status of circuit service and packet service immediate assignment request and the

implementation. Number of TCH seizure requests, the successful TCH seizures, TCH call drops, TCH

seizure requests for very early assignment, successful TCH seizures for very early assignment, TCH call drops for very early assignment, SDCCH seizure requests, successful SDCCH seizures, and SDCCH call drops.

Dedicated measurement for assignment procedure, including the number of unsuccessful assignments due to various causes.

Measurement of TCH MR (measurement report), and independent measurement of very early TCH assignment MR.

Intra-BSC handover request and the implementation of the request, the measurement of incoming BSC handover request and the implementation (including the measurement of the unsuccessful Incoming BSC Handovers due to various causes), outgoing BSC handover request and the implementation, and the measurement of the handover due to various causes.

State statistics of A-interface trunk circuits, including the number of circuits in Not Installed or Faulty state, Idle state, and Busy state, and the percentage of the number to the total number configured.

The measurement of analytical items such as BSC handover success rate, call drop rate, and traffic volume. Many statistic items in BSC Measurement Function have the corresponding items of cell level in Cell Measurement Function. For the traffic status of the specified cell, you can register the related items in Cell Measurement Function. It is recommended that all statistic items in BSC Measurement Function should be registered through 3 tasks after the BSC kickoff because these items are important items for measuring network performance. It is recommended that the templates should be used to register and the traffic statistic cycle should be 60 minutes. 900/850 cell refers to the cell whose main BCCH frequency is 900MHz or 850MHz. 1800/1900 cell refers to the cell whose main BCCH frequency is 1800MHz or 1900MHz.




The statistic object of BSC Measurement Function is the whole BSC. So there is no object option on the object definition interface in OMC traffic statistics console.

3.1.2 Access Measurement Function(1) All the statistic items of Access Measurement Function(1) are listed in.Table 3-1

Table 3-1 Statistic items in Access measurement function items (1)

No. Item name

1 Sum of CM Service Rejections

2 CM Service Rejections due to Congestion

3 CM Service Rejections due to Network Failure

4 CM Service Rejections due to Illegal MS

5 CM service rejections due to error messages

6 CM Service Rejections due to Other Causes

7 Average Interval of Random Accesses

8 Average Interval of Random Accesses for Packet Call

9 Number of PAGING REQUESTs for CS Service on the A Interface

10 Number of PAGING REQUESTs for CS Service on the Pb Interface

11 Number of PAGING REQUESTs for PS Service on the Pb Interface

12 Packet Paging Commands to BTS

13 Successful Circuit Pagings of Abis Interface

14 Circuit Paging PCH Overloads of Abis Interface

15 Circuit Paging RACH Overloads of Abis Interface

16 Packet Paging Commands to BTS

17 Immediate Assignment Requests

18 Radom Access Requests

19 Packet Immediate Assignment Request

20 Immediate Assignment Transmissions

21 Successful Packet Immediate Assignment

22 Successful Connections

23 Attempted TCH Seizures (All)

24 Attempted TCH Seizures (All)

25 Successful TCH Seizures

26 TCH Call Drop



No. Item name

27 Successful TCH Seizures for Early Assignment

28 TCH Drop for Very Early Assignment

29 Attempted SDCCH Seizures (all)

30 Successful SDCCH Seizures

31 Attempted SDCCH Seizures Meeting SDCCH Overflow

32 SDCCH Call Drop

33 Assignment Requests

34 Unsuccessful Assignments

35 Unsuccessful Assignments (Equipment Failure)

36 Unsuccessful Assignments (Requested Terrestrial Resource Unavailable)

37 Unsuccessful Assignments (Terrestrial Circuit Already Allocated)

38 Unsuccessful Assignments (Invalid Message Contents)

39 Unsuccessful Assignments (Radio Interface Failure, Reversion To Previous Channel)

40 Unsuccessful Assignments (No Radio Resource Available)

41 Unsuccessful Assignments (Other Causes)

42 Unsuccessful Channel Activation During Assignment (NACK)

43 Channel Activation Timeout During Assignment

44 Sum of TCH Measurements (Excluding Very Early Assignment)

45 Sum of 1800/1900 Cell TCH Measurements(Excluding Very Early Assignment)

46 Sum of Full Rate TCH Measurements (Excluding Very Early Assignment)

47 Sum of Half Rate TCH Measurements (Excluding Very Early Assignment)

48 Sum of 1800/1900 Cell Full Rate TCH Measurements (Excluding Very Early Assignment)

49 Sum of 1800/1900 Cell Half Rate TCH Measurements (Excluding Very Early Assignment)

50 Sum of Configured TRX in the BSC

51 Sum of Available TRX in the BSC

52 Assignment Requests With Signaling Channel

53 Successful Assignments With Signaling Channel

54 Average number of A-interface circuits(uninstall)

55 Average number of A-interface circuits(Fault)




No. Item name

56 Average number of A-interface circuits(Maintenance)

57 Average number of A-interface circuits(Blocked)

58 Average number of A-interface circuits(Idle)

59 Average number of A-interface circuits(Busy)

60 Average number of A-interface circuits(Opposite Uninstall)

61 Number of Configured A-Interface Circuits

62 Percent of A-Interface Circuit (Uninstall) (%)

63 Percent of A-Interface Circuit (Fault) (%)

64 Percent of A-Interface Circuits (Maintenance) (%)

65 Percent of A-Interface Circuits (Blocked) (%)

66 Percent of A-Interface Circuits (Idle) (%)

67 Percent of A-Interface Circuits (Busy) (%)

68 Percent of A-Interface Circuits (Opposite Uninstall) (%)

69 TCH Channel Allocation Failure (No Available License)

70 Circuit Paging Success Rate

71 Ratio of Paging Channel Overloads (%)

72 Rate of Sending Immediate Assignment Command

73 TCH Call Drop Rate (%)

74 Traffic Volume (Excluding Very Early Assignment) (Erl)

75 Traffic Volume Of 1800/1900 Cell (Excluding Very Early Assignment) (Erl)

76 Percentage of TRX In Good Condition (%)

77 SDCCH Call Drop Rate (%)

78 SDCCH Congestion Rate (SDCCH Overflow) (%)

79 Full Rate Traffic Volume (Excluding Very Early Assignment) (ERL)

80 Half Rate Traffic Volume (Excluding Very Early Assignment) (ERL)

81 Full rate Traffic Volume Of 1800/1900 Cell (Excluding Very Early Assignment) (ERL)

82 Half Rate Traffic Volume Of 1800/1900 Cell (Excluding Very Early Assignment) (ERL)



Sum of CM Service Rejections Description: in the MS originating immediate assignment procedure, first MS and BSS

establish RR connection. Then MS sends the detailed MM service request on MM layer through CM SERVICE REQUEST to network side. This message can carry the following MM service types: Mobile originating call establishment, packet mode connection establishment, emergency call establishment, short message service and supplementary service activation. BSS transparently transmits this message to NSS. If NSS does not support nor does not respond to this service request for some reason, MSC sends CM SERVICE REJECT message to the MS. BSC transparently transmits this message. See GSM 0408 protocol.

Measurement point: as shown in Figure 3-1 A1, when BSC receives the DTAP message of CM SERVICE REJECT from MSC, this item is measured regardless the rejection cause carried in the message.

Formula: none

Figure 3-1 CM SERVICE REQUEST rejection process

A1: Sum of CM service rejections B1: Sum of CM service rejections (congestion) C1: Sum of CM service rejections (network failure) D1: Sum of CM service rejections (illegal MS) E1: Sum of CM service rejections (other reasons) F1: Sum of CM service rejections (error messages)

CM Service Rejections due to Congestion Description: if NSS cannot normally respond to a CM SERVICE REQUEST message

due to the congestion after receiving this message from MS MM layer, NSS responds MS a CM SERVICE REJECT message in which the rejection cause is congestion. See GSM 0408 protocol.

Measurement point: as shown in the B1 in Figure 3-1, this item is measured when BSC receives the DTAP message of CM SERVICE REJECT from MSC and the rejection cause carried in this message is congestion.

Formula: none




CM Service Rejections due to Network Failure Description: if NSS cannot normally respond to a CM SERVICE REQUEST due to

network failure after receiving this message from MS MM layer, NSS responds MS a CM SERVICE REJECT message in which the rejection cause is network failure. See GSM 0408 protocol.

Measurement point: as shown in the C1 in Figure 3-1, BSC measures this item when BSC receives the DTAP message of CM SERVICE REJECT from MSC, the rejection cause carried in this message is network failure.

Formula: none

CM Service Rejections due to Illegal MS Description: if NSS cannot normally respond to a CM SERVICE REQUEST due to

being unable to identify the MS after receiving this message from the MS MM layer, the NSS responds MS a CM SERVICE REJECT message in which the rejection cause is illegal MS. See GSM 0408 protocol.

Measurement point: as shown in the D1 in Figure 3-1, this item is measured when the BSC receives the DTAP message of CM SERVICE REJECT from MSC with the rejection cause carried in this message being illegal MS.

Formula: none

CM service rejections due to error messages Description: if NSS cannot normally respond to a CM SERVICE REQUEST due to error

messages after receiving this message from the MS MM layer, the NSS responds MS a CM SERVICE REJECT message in which the rejection cause is error message. See GSM 0408 protocol.

Measurement point: as shown in the F1 in the Figure 3-1, this item is measured when the BSC receives the DTAP message of CM SERVICE REJECT from MSC with the rejection cause carried in this message being error messages.

Formula: none

CM Service Rejections due to Other Causes Description: if NSS cannot normally respond to a CM SERVICE REQUEST due to the

reasons other than above mentioned ones after receiving this message from MS MM layer, NSS responds MS a CM SERVICE REJECT message. See GSM 0408 protocol.

Measurement point: as shown in the E1 in Figure 3-1, this item is measured when BSC receives the DTAP message of CM SERVICE REJECT from MSC with the rejection cause carried in this message being other than the above mentioned ones.

Formula: none

Average Interval of Random Accesses Description: This item describes the access frequency of calling MS. The RR entity of

the mobile station initiates the immediate assignment procedure by scheduling the sending of CHANNEL REQUEST on the RACH to BTS, then BTS sends CHANNEL REQUIRED to BSC. See GSM 0408.

Measurement point: BSC counts 1 to the number of channel accesses every time it receives CHANNEL REQUIRED message from BTS, and average inter arrival time = measurement period (second)/sum of channel access times within the measurement period.



Formula: Measurement period (second)/sum of channel access times within the measurement period

Unit: Second

Average Interval of Random Accesses for Packet Call Description: This item describes the frequency of PS access frequency with the access

cause being packet call. The RR entity of the mobile station initiates the immediate channel assignment procedure by periodically sending of CHANNEL REQUEST on the RACH to BTS, then BTS sends CHANNEL REQUIRED to BSC. See GSM 0408 protocol.

Measurement point: BSC counts 1 to the number of channel accesses every time BSC receives CHANNEL REQUIRED message from BTS containing access cause "packet call", and average inter of packet arrival time = measurement period (second)/sum of channel packet access times in the measurement period.

Formula: measurement period (second)/sum of channel packet access times within the measurement period

Unit: Second

Number of PAGING REQUESTs for CS Service on the A Interface Description: when an MS under the BSC is called for CS service, the MSC sends the

circuit service PAGING message to page the called MS from the A interface. This item is used to measure the sum of the received PAGING messages in the statistic cycle. The repeated PAGING message is measured repeatedly. See GSM Rec. 08.08.

Measurement point: As shown in Figure 3-2 A1, this item is measured every time BSC receives the circuit PAGING messages from the A interface.

Formula: none

Figure 3-2 Circuit paging process

3. PAGING REQUEST 2. PAGING COMMAND

MS BTS BSC PCU SGSN MSC/VLR

11'. PAGING12'. PAGING

REQUEST 13'. PAGING

REQUEST

A2

4.CHANNEL REQUEST5.CHANNEL REQUIRED

6.CHANNEL ACTIVATION

7. CHANNEL ACKTIVATION ACKNOWLEDGE

8.IMMEDIATE ASSIGN CMMAND9. IMMEDIATE

ASSIGNMENT

10. PAGING RESPONSE

11. EST IND(PAGINGRESPONSE)

C1

A1

B1

1. PAGING

A1: Number of Paging Requests from the MSC for CS service on the A interface A2: Received circuit paging messages from MSC through GS interface




A1: Number of Paging Requests from the MSC for CS service on the A interface B1: Circuit paging commands to BTS C1: Successful circuit paging of Abis interface

Number of PAGING REQUESTs for CS Service on the Pb Interface Description: When an MS under the BSC is called for CS service, the MSC sends the

circuit service PAGING message to page the called MS from the Gb interface. This item is used to measure the sum of the received PAGING messages in the statistic cycle. The repeated PAGING message is measured repeatedly. See GSM Rec. 08.08.

Measurement point: As shown in Figure 3-2 A2, this item is measured every time the BSC receives the circuit PAGING messages from the Pb interface (between Huawei BSC and the PCU).

Formula: None

Number of PAGING REQUESTs for PS Service on the Pb Interface Description: When an MS under the BSC is called for PS service, the MSC sends a PS

PAGING message to page the called MS from the Gb interface. This item is used to measure the sum of the received PAGING messages in a statistic cycle. The repeated PAGING message is measured repeatedly. See GSM Rec. 08.08.

Measurement point: This item is measured every time the BSC receives a PS PAGING message from the Pb interface (between Huawei BSC and the PCU).

Formula: None

Circuit Paging Commands to BTS Description: in the case an MS under the BSC is called for CS service, BSC sends

PAGING COMMAND to the corresponding cell according to the cell identification discriminator after receiving the circuit PAGING message from the MSC or PCU. This item is used to measure the paging delivery times at Abis. See GSM 08.58 and 04.08.

Measurement point: as shown in the Figure 3-2 B1, this item is measured in every cell every time BSC sends PAGING COMMAND message to the corresponding cell.

Formula: none

Successful Circuit Pagings of Abis Interface Description: after a called MS receives PAGING REQUEST message from network side,

the paging response process is implemented. This MS reports ESTABLISH INDICATION, with the cause value PAGING RESPONSE, to MSC if it successfully seizes signaling channel. See GSM 0408 protocol.

Measurement point: as shown in Figure 3-2 C1, this item is measured every time BSC receives PAGING RESPONSE message from MS.

Formula: none

Circuit Paging PCH Overloads of Abis Interface Description: BTS reports CCCH LOAD INDICATION message to BSC when detecting

the overload of PCH, then BSC measures this item and sends OVERLOAD message to MSC simultaneously. See GSM 0858 protocol.



Measurement point: as shown in Figure 3-2 A1, this item is measured when BSC receives CCCH LOAD INDICATION message from BTS with the cause value carried in the message being PCH overload.

Formula: none

Figure 3-3 CCCH overload process

BTS BSC MSC/VLR

CCCH LOAD INDICATION

A1OVERLOADB1

A1:Circuit paging PCH overloads of Abis interface B1: Circuit paging RACH overloads of Abis interface

Circuit Paging RACH Overloads of Abis Interface Description: When detecting RACH overload, BTS reports CCCH LOAD INDICATION

to BSC, then BSC measures this item and implements the internal flow control. Measurement point: as shown in Figure 3-2 B1, this item is measured when BSC

receives CCCH LOAD INDICATION message from BTS with the cause value carried in the message being RACH overload.

Formula: none

Packet Paging Commands to BTS Description: in the case an MS under the BSC is called for packet service, SGSN sends

PAGING REQUEST message to PCU to page this MS. PCU processes this message and then sends PACKET PAGING message to BSC. According to the cell identification discriminator carried in the PACKET PAGING message, BSC sends PACKET PAGING REQUEST message to the corresponding cell. See GSM 0408, 0460, 0360 protocols.

Measurement point: as shown in Figure 3-2 A1, this item is measured in every cell when BSC sends a PACKET PAGING REQUEST message to the corresponding cell.

Formula: none




Figure 3-4 Packet paging process

PACKETPAGING REQUEST

MS BSC+BTS PCU SGSN

PAGING REQUEST

PACKET PAGING

A1

A1: Packet paging commands to BTS

Immediate Assignment Requests Description: when an MS wants to obtain network service due to some reason, this MS

sends CHANNEL REQUEST message to BTS on RACH to request Dedicated Control Channel, then BTS sends CHANNEL REQUIRED to BSC. This item measures all the access cause value of CHANNEL REQUIRED, not including the discarded numbers of immediate assignment requests in flow control.

Measurement point: This item is measured when BSC receives CHANNEL REQUIRED message from BTS, as shown in Figure 3-5A1. The item is measured after flow control. That is to say, the item does not include the discarded numbrs of immediate assignment requests in flow control

.Formula: none.

Figure 3-5 immediate assignment transmission process

MS BTS BSC

1.CHANNEL REQUEST

2.CHANNEL REQUIRED



5.IMMEDIATE ASSIGN CMMAND

A1

B1

A1: Immediate assignment request/ Radom Access Requests B1: Immediate assignment transmissions

Radom Access Requests Description: When an MS wants to obtain network service due to some reason, this MS

sends CHANNEL REQUEST message to BTS on RACH, then BTS sends CHANNEL REQUIRED to BSC.

Measurement point:, This item is measured when BSC receives CHANNEL REQUIRED message from BTS, as shown in Figure3-5A1.



Formula: none

Packet Immediate Assignment Request Description: to request channel for packet service, MS sends CHANNEL REQUEST

message to BTS on RACH and the access cause carried in the message is Packet Call, then BTS sends CHANNEL REQUIRED to BSC. Upon reception of this message, BSC forwards the request to PCU. See GSM 0408 and 0406 protocol.

Measurement point: as shown in Figure 3-6 A1, BSC measures this item when BSC receives CHANNEL REQUIRED message from BTS and if the access cause carried in the message is Packet Call.

Formula: none

Figure 3-6 Packet immediate channel assignment procedure

MS BTS BSC

CHANNEL REQUEST(PACKET CALL)

CHANNEL REQUIRED

IMM EDIATE ASSIGN CMMAND

A1

HUAWEI PCU

Packet Channel Request

Packet Imm ediate Assign Comm and

B1

A1: Packet immediate assignment request B1: Successful packet immediate assignment

Immediate Assignment Transmissions Description: in immediate assignment procedure, upon reception of the CHANNEL

REQUIRED message reported from BTS, BSC allocates and activates a signaling channel for the MS. If BSC receives the CHANNEL ACTIVATION ACKNOWLEDGE message from BTS indicating that the channel is ready, BSC sends an IMMEDIATE ASSIGNMENT COMMAND message informing the MS to access the dedicated signaling channel, which can be either SDCCH or TCH. This item includes all access cause value of CHANNEL REQUIRED.

Measurement point: As shown in Figure 3-6 B1, this item is measured when BSC sends the IMMEDIATE ASSIGN COMMAND message to MS.

Formula: none

Successful Packet Immediate Assignment Description: if the cause value carried in the CHANNEL REQUEST message sent by

MS on RACH is packet call, BSC forwards this message to PCU after receiving the message. PCU initiates PDCH assignment procedure after receiving the forwarded message and sends a Packet Immediate Assign Command message (Huawei Pb interface) to BSC, then BSC converts this message into IMMEDIATE ASSIGN COMMAND of Abis interface to BTS and BTS sends this message to MS. This process is described in Figure 3-6. The measurement point of this item is indicated in B1. See GSM 0408, 0460 protocol.

Measurement point: upon reception of the Packet Immediate Assign Command message from PCU, BSC measures this item and sends IMMEDIATE ASSIGN COMMAND to BTS.

Formula: none




Successful Connections Description: the successful circuit service connection time in immediate assignment

procedure, if CC connection is to be established after MM connection establishment of MOC, MOC sends a SETUP message to the network to request the call setting up; then MSC responds a CALL PROCESSING message to MOC and pages MTC simultaneously. After the MM connection establishment between MSC and MTC, MSC sends a SETUP message to MTC to request the establishment of CC connection. If permitting the call establishment, MTC responds a CALL CONFIRM message to MSC and MSC forwards this message to MOC. Having seized the traffic channel, MTC sends an ALERTING message to MSC and MSC forwards this message to MOC. After that, MTC sends a CONNECT message to MOC after its off-hook, MOC responds the CONNECT ACKNOWLEDGE message. The call is set up and the MOC and MTC enter the conversation state. See GSM 0408, 0858, 0808 protocols for detailed full process of call connection establishment between the calling MS and the called MS.

This statistic item includes the "directed retry" in the channel assignment procedure. If the directed retry takes place in the channel assignment procedure, this item is measured in the cell that actually allocates channel that is destination cell of directed retry.

Measurement point: As shown in Figure 3-6 A’, A’’, this item is measured when BSC receives the DTAP type of CC message CONNECT or CONNECT ACKNOWLEDGE. If MOC and MTC share the same BSC, both MOC and MTC are measured.

Formula: none

Figure 3-7 CC connection establishment process

Ori-M S BSS1 M SC

A1"

1.CM SERVICE REQUEST

BSS2 Term i-M S

3.CALL CONFIRM ED

2.SETUP

4.ALARTING

4.CONNECT

5.CONNECT ACKNOWLEDGE A1'

Note:A1' count in BSS1A1" count in BSS2

A’, A’’: Successful connections

Attempted TCH Seizures (All) Description: in the following procedures, if the requested channel type is TCH, this item

shall be measured after BSC receives a relevant request. − In immediate assignment procedure, MS sends CHANNEL REQUEST to BTS to

request radio channel.



− In assignment procedure and incoming BSC handover procedure, MSC requests radio resource by sending ASSIGNMENT REQUEST or HANDOVER REQUEST to BSC.

− In intra BSC handover, BSC itself requests a new channel for call.




SDCCH handover: Handover happens on SDCCH. Channel reallocation: In the immediate assignment procedure, Huawei BSC supports channel reallocation. BSC initiates radio channel allocation when it receives CHANNEL REQUIRED message from BTS. BSC allocates a TCH if the access cause value of CHANNEL REQUIRED is "emergency call "or "call re-establishment" and BSC supports very early assignment TCH. Otherwise, BSC allocates a SDCCH. BSC reallocates radio channel automatically based on "GSM 0408" if BSC supports very early assignment of TCH and channel allocation fails due to no radio resource available. In other words BSC allocates a TCH automatically if SDCCH allocation fails and the access cause is not "location update", and similarly, BSC allocates a SDCCH automatically if TCH allocation fails. So, to one CHANNEL REQUEST message, BSC measures both SDCCH and TCH seizure times. Very early assignment TCH: If BSC allocates a TCH as a signaling channel in immediate assignment procedure, instead of the traffic channel allocation procedure, the Mode Modify procedure can be implemented in the assignment procedure. Assignment SDCCH: In the assignment procedure, MSC sends ASSIGNMENT REQUEST message to BSC to request for a radio channel. BSC responses ASSIGNMENT COMPLETE message to MSC directly if the channel type in the ASSIGNMENT REQUEST is SDCCH. In this case, BSC implements signaling or short message transmission on the channel already allocated. BSC does not measure either "attempted SDCCH seizures" or "successful SDCCH seizures" for it does not allocate a new channel. Instead, it measures the times of "assignment requests" and "assignment success" after successfully sending ASSIGNMENT COMPLETE message. Discard CHANNLE REQUIRED in internal flow: In the immediate assignment procedure, BSC receives CHANNEL REQUIRED messages from BTS. BSC discards these messages if the system is too busy to respond. In this case, "attempted TCH" or "SDCCH seizures" will be measured but "successful or unsuccessful channel seizures" will not be measured.

Measurement point: the measurement point of this item is described inFigure 3-8, Figure 3-9, Figure 3-10 and Figure 3-11TCH-ATT-BSC1--TCH-ATT-BSC4. − In immediate assignment procedure, this item is measured when BSC receives

CHANNEL REQUIRED message from BTS and the requested channel type is TCH. − In assignment procedure, this item is measured when BSC receives ASSIGNMENT

REQUEST message from MSC and the requested channel type is TCH. − In intra BSC handover, the source cell sends Intercell Handover Request message

(Huawei defined message) to the target cell; if the handover is taken place on TCH, this item is measured when the target cell receives this message. The intra BSC handover includes the case that handover is taken place in the same cell with the originating and the target cell being the same one.

− This item is measured when Huawei BSC receives the HANDOVER REQUEST message from other BSC and the handover is taken place on TCH.

Formula: none



Figure 3-8 Immediate assignment procedure-channel seizure procedure

MS BTS BSC

CHANNEL REQUEST CHANNEL REQUIRED

CHANNEL ACTIVATIONCHANNEL ACKTIVATION ACKNOWLEDGE

TCH-ATT-BSC1

TCH -ATT-BSC1: Attempted TCH seizures (all)

Figure 3-9 Assignment procedure-channel seizure procedure

MS BTS BSC

.ASSIGN CMMAND

MSC

ASSIGNMENT REQUEST

SABM

UAESTABLISH INDICATION

ASSIGNMENT COMPLETE

(directly retry)HANDOVER REQIRED

(directly retry)HANDOVER REQUEST ACK

CHANNEL ACTICATION

CHANNEL ACTIVATION ACK

QUEUEING INDICATIONTCH-ATT-BSC 2





Figure 3-10 Intra-BSC handover channel seizure procedure

MS BTS' BSC Ori-Cell

HANDOVER ACCESS

UA

Intercell Handover Request

BSC Des-Cell BTS''MR

Handover algorithm

HANDOVER COMMAND

Intercell Handover Response

HANDOVER DETECT

CH ACTCH ACT ACK

HANDOVER COMPLETE

Inter Clear Request (Handover Success)

TCH-ATT-BSC3

SABM


Figure 3-11 Incoming BSC handover channel seizure procedure

MS Other BSC

HANDOVER ACCESS

UA

HANDOVER REQUIRED

HUAWEI BSC HUAWEI BTS

HANDOVER COMMANDHANDOVER REQUEST ACK

HANDOVER DETECT

CH ACTCH ACT ACK

HANDOVER COMPLETE

TCH-ATT-BSC4

MSC

QUEUEING INDICATION

HANDOVER REQUEST

SABM


TCH Call Drop Connected Description: this item measures the number of call drop when MS is normally during the

conversation on radio channel. In the assignment procedure and handover procedure, the establishment of a conversation is indicated by: in assignment procedure BSC receives the CONNECT message and the CONNECT ACKNOWLEDGE message from CC layer; in the incoming BSC handover procedure the target cell sends HANOVER COMPLETE message to MSC; successful intra BSC handover: the target cell sends HANDOVER



PERFORMED message to MSC when it detects the access of the MS. If the call drop occurs after the above stages, it will be regarded as call drop connected.

Measurement point: − Upon BSC’s reception of ERROR INDICATION message from BTS due to an

abnormal connection in a radio link layer. See GSM 0508 protocol. − During MS conversation, BTS detects a fault in radio link layer or hardware; it sends

a CONNECTION FAILURE INDICATION message to BSC informing the BSC this failure. See GSM 0508 protocol.

− The timer expires when BSC waiting for the CLEAR COMMAND message from MSC during outgoing BSC handover.

− In Intra-BSC handover procedure, the target cell sends Inter Clear Request to the source cell when the timer for the target cell to wait for HANDOVER COMPLETE from MS expires, in this case, this item is measured in the source cell.

− In Intra-BSC handover procedure, the source cell, excluding the source cell for directed retry, measures the item when the timer for the source cell to wait for Inter Clear Request with cause value HANDOVER COMPLETE from the target cell expires.

− In Intra-BSC handover procedure, when the target cell AM/CM net-drive fails (due to timeout or negative acknowledgement), the target cell sends Inter Clear Request to source cell, in this case, this item is measured in the source cell.

− In the case that MS reverses to the original channel after intra BSC handover fails, the source cell first releases the terrestrial connection but the AM/CM re-net-drive fails (due to timeout or negative acknowledgement). In this case this item is measured in the source cell.

− The resource of the lower_priority call will be preempted by the higher_priority call if MSC and BSC both support preemption, which will cause call drop.

− This item is measured when the RSL link of the TRX that the call is using disconnects, which will cause call drop.

AM/CM net-drive: In assignment procedure or handover procedure, BSC establishes the terrestrial connection in A-interface for a MS after it has successfully allocated radio channel.

Formula: none

Successful TCH Seizures Description: in very early assignment procedure, assignment procedure, and handover

procedure, BSC measures this item when MS successfully seizes the allocated TCH. The successful directed retry is also measured as successful TCH seizure: If there is no available channel after ASSIGNMENT REQUEST message from MSC is sent to the cell of the BSC and the system supports directed retry, then BSC initiates outgoing cell handover according to the information about adjacent cell in MS’s MR.

Measurement point: this item is measured if TCH is successfully seized by the following processes: − Upon BSC’s reception of CHANNEL ACTIVATION ACKNOWLEDGE message

from BTS in very early assignment TCH process. − In the case the target cell of directed retry is located in other BSC and directed retry

succeeds, MSC sends CLEAR COMMAND message to the originating BSC to release the original connection. This item is measured when the originating BSC receives this message.




− In the case the directed retry target cell is located in the same BSC and the directed retry succeeds, target cell sends Inter Clear Request message to the source cell to request to release the resource and the original connection. This item is measured when the source cell receives this message.

− This item is measured when BSC sends ASSIGNMENT COMPLETE message to MSC after the assignment procedure is successfully implemented.

− In incoming BSC handover procedure, MS sends HANDOVER ACCESS message to the BSC. This item is measured when BSC receives HANDOVER DETECT message from BTS.

− In the process of incoming internal inter cell handover and intracell handover in BSC, MS sends HANDOVER ACCESS message to BSC. BSC measures this item in the target cell when receiving HANDOVER DETECTION message from BTS.

Formula: none

TCH Call Drop Description: in assignment procedure and traffic channel handover procedure, BSC

measures TCH call drop when the process implementation fails due to some reason after MS has accessed the TCH assigned by BSC. Or this item is measured when call drop takes place due to some reason when MS is in normal seizure of TCH. After the above cases occur, BSC sends CLEAR REQUEST message to MSC to request to clear the call.

Measurement point: this item is measured if call drop occurs on TCH in the following processes.Figure 3-12, Figure 3-13, Figure 3-14 A1 and A2 indicate the main measurement points. − In the case TCH serves as traffic channel, this item is measured when BSC receives

ERROR INDICATION message from BTS due to an abnormal case for a radio link layer connection. See GSM 0858 protocol.

− In the case TCH is seized as traffic channel, this item is measured when BSC receives the CONNECT FAILURE INDICATION message from BTS due to an active connection has been broken for some reason such as TCH link failure or hardware failure etc. See GSM 0508 for details.

− In the case TCH serves as traffic channel, this item is measured when incoming BSC handover is initiated and the timer for the target cell to wait for HANDOVER COMPLETE message expires.

− In the case TCH serves as traffic channel, this item is measured when outgoing BSC handover is initiated and the timer for the source cell to wait for CLEAR COMMAND message from MSC expires (T8 expires).

− In Intra-BSC handover procedure, the target cell sends Inter Clear Request to the source cell when the timer for the target cell to wait for HANDOVER COMPLETE from MS expires, in this case, this item is measured in the source cell.

− In Intra-BSC handover procedure, the source cell, excluding the source cell for directed retry, measures the item when the timer for the source cell to wait for Inter Clear Request with cause value HANDOVER COMPLETE from the target cell expires.

− In Intra-BSC handover procedure, when the target cell AM/CM net-drive fails (due to timeout or negative acknowledgement), the target cell sends Inter Clear Request to source cell, in this case, this item is measured in the source cell.

− In the case that MS reverses to the original channel after intra BSC handover fails, the source cell first releases the terrestrial connection but the AM/CM re-net-drive fails (due to timeout or negative acknowledgement). In this case this item is measured in the source cell.



− The resource of the lower_priority call will be preempted by the higher_priority call if MSC and BSC both support preemption, which will cause call drop.

− This item is measured when the RSL link of the TRX that the call is using disconnects, which will cause call drop.

Formula: none.

Figure 3-12 TCH drop for assignment

MS BTS BSC

ASSIGN CMMAND

MSC

ASSIGNMENT REQUEST

SABM


CHANNEL ACTICATION

CHANNEL ACTIVATION ACK

A1ERROR INDICATION

CONNECTION FAILURE INDICATION

A2

A1, A2: TCH call drop (BSC)

Figure 3-13 Drop for Intra BSC handover

MS BSC' BSC Ori-Cell

HANDOVER ACCESS

UA


BSC Tag-Cell BSC''

HANDOVER COMMAND


HANDOVER DETECT

CH ACT

CH ACT ACK

A1

ERROR INDICATION


A2

SABM

A1, A2: TCH drop for very early assignment (BSC), TCH call drop (BSC)




Figure 3-14 Incoming BSC TCH handover procedure

MS Other BSC

HANDOVER ACCESS

UA

HANDOVER REQUIRED



HANDOVER DETECT

CH ACTCH ACT ACK

MSC

A1ERROR INDICATION


A2

SABM

HANDOVER REQUEST

A1, A2: TCH drop for very early assignment (BSC), TCH call drop (BSC)

Successful TCH Seizures for Early Assignment Description: BSC measures this item when MS successfully seizes the TCH assigned by

the network in early assignment procedure (including the MS access for various reasons).

Measurement point: the measurement points of this item are indicated in Figure 3-15 A1. This item is measured when BSC receives CHANNEL ACTIVATION ACKNOWLEDGE message from BTS in early assignment TCH process.

Formula: none

Figure 3-15 Successful TCH seizures for very early assignment procedure

MS BTS BSC

1.CHANNEL REQUEST

2.CHANNEL REQUIRED



5.IMMEDIATE ASSIGN CMMAND A1

ESTABLISH INDICATION(SAPI=0)

A1:Successful TCH seizures for very early assignment



TCH Drop for Very Early Assignment Description: In intraBSC or inter BSC handover procedure, if a handover occurs on TCH

and the speech data indication is signaling, this handover is regarded as a signaling channel handover. BSC measures this item if MS has accessed the TCH assigned by BSC but the implementation of the signaling channel handover fails due to some reason. BSC also measures this item when call drop occurs due to some reason after MS has established the normal connection on TCH and the speech data indication is signaling. When the above cases occur, BSC sends a CLEAR REQUEST message to MSC to clear the current connection.

Measurement point: this item is measured if the channel type in the following cases is TCH. The A1 and A2 in Figure 3-13 ,Figure 3-14 and Figure 3-16 indicate the main measurement points of this item. − In the case TCH is seized as signaling channel, this item is measured when BSC

receives ERROR INDICATION message from BTS due to an abnormal case for a radio link layer connection. See GSM 0858 protocol.

− In the case TCH is seized as signaling channel, this item is measured when BSC receives CONNECTION FAILURE INDICATION message from BTS due to an active connection has been broken for some reason such as TCH link failure or hardware failure etc. See GSM 0858 protocol for details.

− In the case TCH is seized as signaling channel, in incoming BSC handover procedure, this item is measured in the target cell in the case of the failure of decoding HANDOVER DETECTION and HANDOVER COMPLETE message.

− In the case TCH serves as signaling channel, this item is measured when incoming BSC handover is initiated and the timer for the target cell to wait for HANDOVER COMPLETE message expires.

− In the case TCH serves as signaling channel, this item is measured when outgoing BSC handover is initiated and the timer for the source cell to wait for CLEAR COMMAND message from MSC expires (T8 expires).

− In the case TCH is seized as signaling channel, in Intra-BSC handover procedure, this item is measured in the source cell when the timer for the target cell or the source cell to wait for HANDOVER COMPLETE expires.

− In the case TCH is seized as signaling channel, The resource of the lower_priority call will be preempted by the higher_priority call if MSC and BSC both supports preemption, which will cause call drop.

− In the case TCH is seized as signaling channel, this item is measured when the RSL link of the TRX that the call is using disconnects, which will cause call drop.

Formula: none




Figure 3-16 TCH drop for very early assignment

MS BTS BSC

CHANNEL REQUEST CHANNEL REQUIRED


IMMEDIATE ASSIGN CMMAND

EST_IND

A1

SABMUA

ERROR INDICATION

CONNECTION FAILURE INDICATIONA2

A1, A2: TCH drop for very early assignment (BSC)

Attempted SDCCH Seizures (all) Description: in immediate assignment procedure, MS sends CHANNEL REQUEST to

BTS to request radio channel. In incoming BSC handover procedure, MSC requests radio resource by sending HANDOVER REQUEST to BSC. In intra BSC handover, BSC itself requests a new channel for call. In those cases, this item is measured when BSC receives SDCCH allocation request.

Measurement point: the measurement point of this item is described in Figure 3-17, Figure 3-18 and Figure 3-19 SD-ATT-BSC1--SD-ATT- BSC3. − In immediate assignment procedure, BSC measure this item when it receives

CHANNEL REQUIRED message from MS and if the requested channel type is SDCCH.

− For intra BSC handover on SDCCH, this item is measured when the target cell receives Intercell Handover Request message (Huawei defined message) from the source cell.

− This item is measured if when Huawei BSC receives HANDOVER REQUEST message from other BSC and the handover is taken place on SDCCH.

Formula: none



Figure 3-17 Immediate assignment procedure-channel seizure procedure

MS BTS BSC

CHANNEL REQUEST

CHANNEL REQUIRED


IM M EDIATE ASSIGN CM M AND

SD-ATT-BSC1

EST_IND

SD -ATT-BSC1: Attempted SDCCH seizures (all)


MS BTS' BSC Ori-Cell

HANDOVER ACCESS

UA


BSC Des-Cell BTS''MR

Handover algorithm

HANDOVER COMMAND


HANDOVER DETECT

CH ACTCH ACT ACK

HANDOVER COMPLETE

Inter Clear Request(Handover Success)

SD-ATT-BSC2

SABM

SD-ATT-BSC2: Attempted SDCCH seizures (all)





MS Other BSC

HANDOVER ACCESS

UA

HANDOVER REQUIRED



HANDOVER DETECT

CH ACTCH ACT ACK

HANDOVER COMPLETE

SD-ATT-BSC3

MSC

QUEUEING INDICATION

SABM

HANDOVER REQUEST

SD -ATT-BSC3: Attempted TCH seizures (all)

Successful SDCCH Seizures Description: in immediate assignment procedure, assignment procedure, and handover

procedure, this item is measured when BSC receives the notification from MS that MS has successfully seized the assigned SDCCH.

Measurement point: − In immediate SDCCH assignment procedure, this item is measured when BSC

receives CHANNEL ACTIVATION ACKNOWLEDGE message from BTS. − In the process of incoming BSC handover on SDCCH, BTS sends HANDOVER

DETECTION message to BSC. This item is measured when BSC receives HANDOVER DETECTION.

− In the process of incoming internal inter cell handover and intracell handover in BSC, BTS sends HANDOVER DETECTION message to BSC. BSC measures this item in the target cell when receiving this message.

Formula: none

Attempted SDCCH Seizures Meeting SDCCH Overflow Description: in immediate assignment procedure and handover procedure, this item is

measured if there is no available SDCCH for assignment when MS or MSC requests BSS to assign SDCCH.

Measurement point: this item is measured if there is no available SDCCH when SDCCH is requested in the following cases: − BSC receives CHANNEL REQUIRED message from BTS. − BSC receives Intercell Handover Request message from other cell in the same BSC. − BSC receives HANDOVER REQUEST message from other BSC.

Formula: none



SDCCH Call Drop Description: in immediate assignment procedure and handover procedure, BSC measures

SDCCH call drop when the process implementation fails due to some reason after MS has accessed the SDCCH assigned by BSC. Or this item is measured when call drop takes place due to some reason when MS is in normal seizure of SDCCH. After the above cases occur, BSC sends CLEAR REQUEST message to MSC.

Measurement point: − This item is measured when BSC receives ERROR INDICATION message from BTS

due to an abnormal case for a radio link layer connection. − This item is measured when BSC receives CONNECTION FAILURE INDICATION

message from BTS because an active connection has been broken for some reason such as SDCCH link failure or hardware failure (see GSM 0508 for details).

− In incoming BSC handover procedure on SDCCH, this item is measured in the target cell in the case of the failure of decoding HANDOVER DETECTION and HANDOVER COMPLETE message.

− In the process of incoming BSC handover on SDCCH, this item is measured in the target cell when the timer for the target cell to wait for the HANDOVER COMPLETE message expires.

− In the process outgoing BSC handover on SDCCH, this item is measured when the timer for the source cell to wait for CLEAR COMMAND message from MSC expires (T8 expires).

− In the process of intra BSC handover on SDCCH, this item is measured in the source cell when the timer for the source cell or the target cell to wait for HANDOVER COMPLETE message expires.

− This item is measured when the RSL link of the TRX that the call is running on disconnect, which will cause call drop, this item measures call drop on SDCCH for RSL disconnection.

Formula: none

Assignment Requests Description: the initial random access by the MS and "Immediate Assignment" to a

DCCH is handled autonomously by the BSS without reference to the MSC. After the RR connection is established between MS and BSS, MS establishes the MM and CC connection with MSC on this channel. MSC allocates or reallocates to the MS a radio (and possibly terrestrial) resource in ASSIGNMENT REQUEST message according to MS’s CC connection request.

Measurement point: as shown in Figure 3-20 A1, this item is measured when BSC receives ASSIGNMENT REQUEST message from MSC.

Formula: none




Figure 3-20 Assignment implementation process

MS BTS BSC

ASSIGN CMMAND

A1

MSC

ASSIGNMENT REQUEST

SABM


ASSIGNMENT COMPLETE

(directly retry)HANDOVER REQIRED

MODE (MODIFY)MODE (MODIFY) ACKNOLEDGE(NEGATIVE ACKNOWLEDGE,REJECT)

(directly retry)HANDOVER FAILURE(REQUEST ACKNOWLEDGE)

CHANNEL ACKTIVATION

CHANNEL ACKTIVATION ACKNOWLEDGE (NACK)

ASSIGNMENT COMPLETE

In Immediate Assignment or IntraBSC Handover

ASS FAILURE

H 4

B 2

B 3 B 4 B 5

C1

C 2

D1 E1

F1

F1

F2

F3

F3

F3

G1

G 2 G 3

G4

G6

G5

G5

B6

H 2

H 3

H 3

ASS FAILURE

ASS FAILURE

A1: Assignment requests B2-B6: Unsuccessful assignments (equipment failure) C1-C2: Unsuccessful assignments (requested terrestrial resource unavailable)

D1: Unsuccessful assignments (terrestrial circuit already allocated)

E1:Unsuccessful assignments (invalid message contents))

F1-F3: Unsuccessful assignments (radio interface failure, reversion to previous channel))

G1-G6: Unsuccessful assignments (no radio resource available))

H2-H4: Unsuccessful assignments (other causes))

Unsuccessful Assignments Description: BSS might fail to implement the assignment procedure due to some reason

after receiving ASSIGNMENT REQUEST message from MSC.



The relation between queues, directed retry and mode modify in assignment procedure. In assignment procedure, upon reception of ASSIGNMENT REQUEST message, BSC first checks CIC resource, then analyzes the CHANNEL TYPE in the message (See GSM 0808), at last compares the analyzed CHANNEL TYPE with the currently seized one. The comparison result leads to three types of options: mode modify, directed retry, or requesting a new channel. CHANNEL TYPE contains channel rate and type and traffic type (speech/data indicator), speech encoding algorithm and transparency indicator. The channel re-allocation is initiated if the channel rate or type is different. The mode modify is initiated if the traffic type (speech/data indicator), or speech encoding algorithm/transparency indicator is different. If all are consistent, the system uses the existing radio channel and allocates CIC for BSC net-drive. So there are 5 subsequent processes after the reception of ASSIGNMENT REQUEST. 1. Mode modify. 2. Queue (if there is no available channel during re-allocation and the system supports queue). 3. Directed retry (if there is no available channel during re-allocation and the system supports directed retry). 4. No available channel after the queue timeout; directed retry again if the system supports directed retry. 5. Normal assignment: new channel is assigned, activated, and then is normally seized by the MS.

Measurement point: as shown in Figure 3-20 if BSS fails to respond to ASSIGNMENT COMPLETE message to MSC due to some reason after receiving ASSIGNMENT REQUEST message, this item is measured and BSS responds ASSIGNMENT FAILURE message to MSC simultaneously. Figure 3-20 shows the reasons for unsuccessful assignment. This item is measured for the unsuccessful assignment caused by any of these reasons.

Formula: none

Unsuccessful Assignments (Equipment Failure) Description: the sum of unsuccessful assignments due to equipment failure. See

Unsuccessful Assignments for the process. Measurement point: as shown in Figure 3-20 B2~B6, this item is measured in the

following case. − In assignment procedure, BSC assigns terrestrial circuit according to the CIC

specified by MSC but the assignment fails. In this case, this item is measured and BSC requests MSC to clear the connection simultaneously.

− In assignment procedure, this item is measured if BSC’s AM/CM net-drive fails (AM/CM returns net-drive failure or responds timeout) after the mode modify is implemented and the radio channel has been successfully modified according to the CHANNEL TYPE required by MSC.

− If mode modify is initiated in assignment procedure, this item is measured when BSC receives MODE MODIFY NEGATIVE ACKNOWLEDGE message from BTS indicating the failure of mode modify after the MODE MODIFY message is sent to BTS.

− If mode modify is initiated in assignment procedure, this item is measured when the timer for BSC to wait for the response expires after the MODE MODIFY message has been sent to BTS.

− In assignment procedure, this item is measured when BSC receives Channel Activation NACK or the timer for BSC to wait for Channel Activation ACK expires.

Formula: none




Unsuccessful Assignments (Requested Terrestrial Resource Unavailable) Description: Unsuccessful assignments due to the requested terrestrial resource

unavailable. See Unsuccessful Assignments for the process. Measurement point: as shown in Figure 3-20 C1~C2:

− This item is measured when BSC detects the state of CIC requested in the ASSIGNMENT REQUEST message received from MSC is unavailable.

− This item is measured when AM/CM net-drive fails (AM/CM returns net-drive rejection or timer for waiting for AM/CM expires) in assignment procedure,.

− Formula: none

Unsuccessful Assignments (Terrestrial Circuit Already Allocated) Description: unsuccessful assignments due to terrestrial circuit already allocated. See

Unsuccessful Assignments for the process. Measurement point: as shown in Figure 3-20 D1, in assignment procedure, this item is

measured when BSC detects the CIC requested in the ASSIGNMENT REQUEST message received from MSC has already been allocated.

Formula: none

Unsuccessful Assignments (Invalid Message Contents) Description: unsuccessful assignments due to invalid message contents. See

Unsuccessful Assignments for the process. Measurement point: as shown in Figure 3-20 E1, this item is measured when BSC

detects the ASSIGNMENT REQUEST message contains invalid contents during the message decoding, Which includes CHANNEL TYPE, CIC, Layer 3 header information.

Formula: none

Unsuccessful Assignments (Radio Interface Failure, Reversion To Previous Channel)

Description: unsuccessful assignments due to radio interface failure with reversion to previous channel

Measurement point: as shown in Figure 3-20 F1-F3: − BSC measures this item when MS fails to access the new channel and reverses to the

old signaling channel due to Um interface failures after it receives the ASSIGNMENT COMMAND message.

− in assignment procedure, after sending the ASSIGNMENT COMMAND message, if the timer for BSC to wait for ASSIGNMENT COMPLETE message from MS expires, BSC measures this item and informs MSC to clear the connection simultaneously.

Formula: none

Unsuccessful Assignments (No Radio Resource Available) Description: unsuccessful assignments due to no radio resource available. See

Unsuccessful Assignments for the process. Measurement point: as shown in Figure 3-20 G1-G6,

− This item is measured when BSC does not support the assigned channel.



− This item is measured if there is no available channel when BSC assigns the channel after receiving ASSIGNMENT REQUEST message and BSC does not support queue and directed retry.

− If mode modify is initiated in assignment procedure, the CHANNEL MODE MODIFY message is sent to the MS, then the MS implement mode modify and response CHANNEL MODE MODIFY ACKNOWLEDGE to BSC. This item is measured when BSC receives this message from MS but meets error when decode channel mode IE.

− If there is no available channel when BSC receives ASSINGMENT REQUEST message and the system supports queue, the assignment procedure waits for channel resource; if idle channel is available before the timer expires, the system allocates the channel successfully and the assignment procedure goes normally; if there still no available channel resource after the timer expires and the call doesn’t support directed retry, BSC measures the unsuccessful assignment due to channel unavailable.

− If directed retry fails, this item is measured and ASSIGNMENT FAILURE message is sent to MSC to request to clear the connection if the source cell of directed retry is in one of the following cases.

a) There is no available target cell in the MR reported from MS, for directed retry selects the target cell of handover according to the MR.

b) This item is measured in the source cell if the source cell receives Intercell Handover Reject message from the target cell when directed retry is trying to select other cell in the BSC.

c) This item is measured in the source cell if the MS reverses to the original signaling channel when directed retry is trying to select other cell in the BSC.

d) This item is measured in the source cell when the timer for source cell to wait for response from target cell expires when directed retry is trying to select other cell in the BSC.

e) When directed retry is trying to select other cell in the BSC, the source cell receives Inter Clear Request message (Huawei defined message) from the target cell. However this message is not the one to inform the handover completion but to inform the source cell of the directed retry failure and to request to clear the connection. In this case, this item is measured in the source cell.

f) When directed retry is trying to select other cell in the BSC, the source cell sends HANDOVER COMMAND to MS to request the MS to access the new channel. This item is measured if the source cell has not received Inter Clear Request message (Huawei defined message) from the target cell after the timer expires.

If directed retry is trying to select the target cell in other BSC and the directed retry process fails, the source cell does not return assignment failure and the failure is not measured as an assignment failure item. The failure is processed according to handover procedure.

Formula: none

Unsuccessful Assignments (Other Causes) Description: unsuccessful assignments due to the following causes. See Unsuccessful

Assignments for the process. Measurement point: as shown in Figure 3-20 H2-H4,

− When BSC detects IEs, such as, channel rate and type, speed encoding algorithm, is incorrectly described in ASSIGNMENT REQUEST message.




− In assignment procedure, BSC measures the item if the timer for BSC to wait for ESTABLISH INDICATION expires when the ASSIGNMENT COMMAND message has been sent to MS In this case BSC sends clear request to MSC to clear the connection simultaneously.

− If mode modify is initiated in assignment procedure, BSC does not receive the acknowledge message from MS after sending mode modify message, which leads to the timeout of BSC.

Formula: none

Unsuccessful Channel Activation During Assignment (NACK) Description: See Unsuccessful Assignments. Measurement point: this item is measured when BSC receives CHANNEL

ACTIVATION NEGATIVE ACKNOWLEDGE message from BTS after sending CHANNEL ACTIVATION message to BTS to activate the newly- allocated channel.

Formula: none

Channel Activation Timeout During Assignment Description: See Unsuccessful Assignments. Measurement point: this item is measured when the timer for BSC to wait for

CHANNEL ACTIVATION ACKNOWLEDGE from BTS expires after sending CHANNEL ACTIVATION message to BTS to activate the newly- allocated channel.

Formula: none

Sum of TCH Measurements (Excluding Very Early Assignment) Description: This item measures the number of occupied TCH of BSC within the

measurement period (excluding the very early assignment). This item reflects the situation that the MSs within a BSC occupy the TCH resources from the aspect of occupied TCH number.

Measurement point: the system measures the busy TCH number (excluding the very early assignment) every 5 seconds and sums the measurement value of each sampling point and then divides the total value by the sampling times.

Formula: none

Sum of 1800/1900 Cell TCH Measurements(Excluding Very Early Assignment) 1. Description: This item measures the number of occupied TCH of 1800/1900 cell within

the measurement period (excluding the very early assignment). This item reflects the situation that the MSs within an 1800/1900 cell occupy the TCH resources from the aspect of occupied TCH number.

Measurement point: the system measures the busy TCH number (excluding the very early assignment) every 5 seconds and sums the measurement value of each sampling point and then divides the total value by the sampling times..

Formula: none

Sum of Full Rate TCH Measurements (Excluding Very Early Assignment) Meaning: This item measures the number of occupied full rate TCH of BSC within the

measurement period (excluding the very early assignment). This item reflects the



situation that the MSs within a BSC occupy the full rate TCH resources from the aspect of occupied full rate TCH number.

Measurement point: the system measures the busy full rate TCH number (excluding the very early assignment) every 5 seconds and sums the measurement value of each sampling point and then divides the total value by the sampling times.

Formula: None.

Sum of Half Rate TCH Measurements (Excluding Very Early Assignment) Meaning: This item measures the number of occupied half rate TCH of BSC within the

measurement period (excluding the very early assignment). This item reflects the situation that the MSs within a BSC occupy the half rate TCH resources from the aspect of occupied half rate TCH number.

Measurement point: the system measures the busy half rate TCH number (excluding the very early assignment) every 5 seconds and sums the measurement value of each sampling point and then divides the total value by the sampling times.

Formula: None.

Sum of 1800/1900 Cell Full Rate TCH Measurements (Excluding Very Early Assignment)

Meaning: This item measures the number of occupied full rate TCH of 1800/1900 cell within the measurement period (excluding the very early assignment). This item reflects the situation that the MSs within an 1800/1900 cell occupy the full rate TCH resources from the aspect of occupied full rate TCH number.

Measurement point: the system measures the busy full rate TCH number (excluding the very early assignment) every 5 seconds and sums the measurement value of each sampling point and then divides the total value by the sampling times.

Formula: None.

Sum of 1800/1900 Cell Half Rate TCH Measurements (Excluding Very Early Assignment)

Meaning: This item measures the number of occupied half rate TCH of 1800/1900 cell within the measurement period (excluding the very early assignment). This item reflects the situation that the MSs within an 1800/1900 cell occupy the half rate TCH resources from the aspect of occupied half rate TCH number.

Measurement point: the system measures the busy half rate TCH number (excluding the very early assignment) every 5 seconds and sums the measurement value of each sampling point and then divides the total value by the sampling times.

Formula: None.

Sum of Configured TRX in the BSC Description: the sum of actually configured TRXs in the BSC. Measurement point: the configured TRXs that are shown in statistic database as "install"

are measured every time at the end of a statistic cycle. Formula: none

Sum of Available TRX in the BSC Description: sum of TRXs that managed by BSC and are in normal use state.




Measurement point: this item is measured at the end of a statistic cycle. Formula: none

Assignment Requests With Signaling Channel Meaning: When there is a short message sent to a MS which is engaged in a conversation

(seizing a TCH), MSC may issue ASSIGNMENT REQUEST to assign a signaling channel for short message transmission. Since MS has already seized voice channel after channel assignment, and this voice channel can be used to send short message, BSC only needs to return ASSIGNMENT COMPLETE to MSC indicating that channel assignment is completed. After conversation and short message is complete, MSC issues CLEAR COMMAND to initiate release procedure. This item provides the times of ASSIGNMENT REQUEST from MSC to BSC being used to establish signaling connections.

Measurement point: As shown in Figure 3-21 A, this item is measured when BSC receives ASSIGNMENT REQUEST from MSC which is used to assign resource for signaling connection establishment.

Formula: None.

Figure 3-21 Signaling channel request procedure

BSC

A

MSC

B

ASSIGNMENT REQUEST

ASSIGNMENT COMPLETE

ACTIVE CALL

A: Times of signaling channel assignment request B: Times of successful signaling channel assignment

Successful Assignments With Signaling Channel Meaning: When there is a short message sent to a MS which is engaged in a conversation

(seizing a TCH), iMSC may issue ASSIGNMENT REQUEST to assign a signaling channel for short message transmission. Since MS has already seized voice channel after channel assignment, and this voice channel can be used to send short message, BSC only needs to return ASSIGNMENT COMPLETE to MSC indicating that channel assignment is completed. After conversation and short message is complete, MSC issues CLEAR COMMAND to initiate release procedure. This item provides the times of ASSIGNMENT REQUEST from MSC to BSC beng used to establish signaling connections, and after which BSC returns ASSIGNMENT COMPLETE to MSC.

Measurement point: As shown in Figure 3-21 B, this item is measured when BSC returns ASSIGNMENT COMPLETE to MSC after BSC receives ASSIGNMENT REQUEST from MSC which is used to assign resource for signaling connection establishment.

Formula: None.



Average number of A-interface circuits(uninstall) Meaning: the average circuit number that are in the “not installed” state in the A interface

within a statistic period. Measurement point: BSC measures the circuit number that are in the unconfigured state

in the A interface every 5 seconds. Formula: None.

Average number of A-interface circuits(Fault) Meaning: the average circuit number that are in the faulty state in the A interface within a

statistic period. Measurement point: BSC measures the faulty circuit number in the A interface every 5

seconds. Formula: None.

Average number of A-interface circuits(Maintenance) Meaning: the average circuit number that are in the maintenance state in the A interface

within a statistic period. Measurement point: BSC measures the circuit number that are in the maintenance state

in the A interface every 5 seconds. Formula: None.

Average number of A-interface circuits(Blocked) Meaning: the average circuit number whose local ends are in the blocked state in the A

interface within a statistic period. Measurement point: BSC measures the circuit number whose local ends are in the

blocked state in the A interface every 5 seconds. Formula: None.

Average number of A-interface circuits(Idle) Meaning: the average circuit number that are in the idle state in the A interface within a

statistic period. Measurement point: BSC measures the circuit number that are in the idle state in the A

interface every 5 seconds. Formula: None.

Average number of A-interface circuits(Busy) Meaning: the average circuit number that are in the busy state in the A interface within a

statistic period. Measurement point: BSC measures the circuit number that are in the busy state in the A

interface every 5 seconds. Formula: None.

Average number of A-interface circuits(Opposite Uninstall) Meaning: the average circuit number whose peer ends are in the “not installed” state in

the A interface within a statistic period.




Measurement point: BSC measures the circuit number whose peer ends are in the blocked state in the A interface every 5 seconds.

Formula: None

Number of Configured A-Interface Circuits Meaning: the average circuit number in the A interface within a statistic period. Measurement point: None. Formula: Average+Average number of A-interface circuits+Average number of

A-interface circuits+Average number of A-interface circuits(Blocked) + Average number of A-interface circuits(Idle) + Average number of A-interface circuits(Busy) + Average number of A-interface circuits(Opposite Uninstall)

Percent of A-Interface Circuit (Uninstall) (%) Meaning: the ratio of Average number of A-interface circuits to Number of Configured

A-Interface Circuits. Measurement point: None. Formula: Average / Number of Configured A-Interface Circuits

Percent of A-Interface Circuit (Fault) (%) Meaning: the ratio of Average number of A-interface circuits to Number of Configured

A-Interface Circuits Measurement point: None. Formula: Average / Number of Configured A-Interface Circuits

Percent of A-Interface Circuits (Maintenance) (%) Meaning: the ratio of Average number of A-interface circuits to Number of Configured

A-Interface Circuits Measurement point: None. Formula: Average / Number of Configured A-Interface Circuits

Percent of A-Interface Circuits (Blocked) (%) Meaning: the ratio of Average number of A-interface circuits(Blocked) to Number of

Configured A-Interface Circuits Measurement point: None. Formula: Average / Number of Configured A-Interface Circuits

Percent of A-Interface Circuits (Idle) (%) Meaning: the ratio of Average number of A-interface circuits(Idle) to Number of

Configured A-Interface Circuits Measurement point: None. Formula: Average / Number of Configured A-Interface Circuits

Percent of A-Interface Circuits (Busy) (%) Meaning: the ratio of Average A-interface circuits (Busy) to Number of Configured

A-Interface Circuits



Measurement point: None. Formula: Average A-interface circuits (Busy) / Number of Configured A-Interface

Circuits

Percent of A-Interface Circuits (Opposite Uninstall) (%) Meaning: the ratio of Average number of A-interface circuits(Opposite Uninstall) to

Number of Configured A-Interface Circuits Measurement point: None. Formula: Average / Number of Configured A-Interface Circuits

TCH Channel Allocation Failure (No Available License) Meaning: because no idle half rate is available. Measurement Point: this item is measured when there is no available TCH when License

controls BSC to request TCH. Formula: none.

Circuit Paging Success Rate Description: See Successful Circuit Pagings of Abis Interface and Number of PAGING

REQUESTs for CS Service on the A Interface and Number of PAGING REQUESTs for CS Service on the Pb Interface.

Measurement point: none. Formula: Successful circuit paging of Abis interface / (Number of PAGING REQUESTs

for CS Service on the A Interface + Number of PAGING REQUESTs for CS Service on the Pb Interface.)

Ratio of Paging Channel Overloads (%) Description: This item measures the percentage of PCH overloads in the paging

commands to BTS. See Interface, and Packet Paging Commands to BTS. Measurement point: none. Formula: Circuit paging PCH overloads of Abis interface / (Circuit paging commands to

BTS + Packet paging commands to BTS)

Rate of Sending Immediate Assignment Command Description: See Immediate Assignment Transmissions and Immediate Assignment

Requests. Measurement point: none. Formula: Immediate assignment transmissions / Immediate assignment requests

TCH Call Drop Rate (%) Description: This item measures the percentage of TCH call drops in successful TCH

seizures. See TCH Call Drop and Successful TCH Seizures. Measurement point: none. Formula: TCH call drop / Successful TCH seizures




Traffic Volume (Excluding Very Early Assignment) (Erl) Description: This item measures the total traffic volume of all cells in a BSC, excluding

the traffic volume during very early assignment, that is the average number of busy TCHs(excluding very early assignment) after all TCHs of all cells are scaned.

Measurement point: None. Formula: None.

Traffic Volume Of 1800/1900 Cell (Excluding Very Early Assignment) (Erl) Description: This item measures the total traffic volume of all GSM 1800/1900 cells in a

BSC, excluding the traffic volume during very early assignment, that is the average number of busy TCHs(excluding very early assignment) of 1800/1900 cells after all TCHs of all 1800/1900 cells are scaned.

Measurement point: none. Formula: None.

Percentage of TRX In Good Condition (%) Description: This item measures the percentage of good TRXs in total configured TRXs.

See Sum of Available TRX in the BSC and Sum of Configured TRX in the BSC. Measurement point: none. Formula: Sum of available TRX in the BSC / Sum of configured TRX in the BSC

SDCCH Call Drop Rate (%) Description: This item measures the percentage of SDCCH call drops successful

SDCCH seizures. See SDCCH Call Drop and Successful SDCCH Seizures. Measurement point: none. Formula: SDCCH call drop / Successful SDCCH seizures

SDCCH Congestion Rate (SDCCH Overflow) (%) Description: This item measures the percentage of the attempted SDCCH seizures

meeting congestion in total attempted SDCCH seizures. See Attempted SDCCH Seizures Meeting SDCCH Overflow and Attempted SDCCH Seizures (all).

Measurement point: none. Formula: Attempted SDCCH seizures meeting an SDCCH blocked state / Attempted

SDCCH seizures (all)

Full Rate Traffic Volume (Excluding Very Early Assignment) (ERL) Meaning: This item provides the traffic volume on full rate TCHs of all cells (including

900/850 and 1800/1900) of the measured BSC, excluding the traffic on full rate TCH of very early assignment, that is, the average number of busy full rate TCHs(excluding very early assignment) after all full rate TCHs of all cells are scaned.

Measurement point: None. Formula:None



Half Rate Traffic Volume (Excluding Very Early Assignment) (ERL) Meaning: This item provides the traffic volume on half rate TCHs of all cells (including

900/850 and 1800/1900) of the measured BSC, excluding the traffic on half rate TCH of very early assignment, that is, the average number of busy half rate TCHs (excluding very early assignment) after all half rate TCHs in all cells are scaned

Measurement point: None. Formula:None.

Full rate Traffic Volume Of 1800/1900 Cell (Excluding Very Early Assignment) (ERL)

Meaning: This item provides the traffic volume on full rate TCHs of all 1800/1900 cells of the measured BSC, excluding the traffic on full rate TCH of very early assignment, that is, the average number of busy full rate TCHs (excluding very early assignment) after all full rate TCHs of 1800/1900 cells are scaned.

Measurement point: None. Formula: None.

Half Rate Traffic Volume Of 1800/1900 Cell (Excluding Very Early Assignment) (ERL)

Meaning: This item provides the traffic volume on half rate TCHs of all 1800/1900 cells of the measured BSC, excluding the traffic on half rate TCH of very early assignment, that is, the average number of busy half rate TCHs (excluding very early assignment) after all half rate TCHs in 1800/1900 cells are scaned.

Measurement point: None. Formula: None

3.1.3 Access Measurement Function(2) All the statistic items of Access Measurement Function (2) are listed in Table 3-2.

Table 3-2 Statistic items in Access measurement function items(2)

1 Configured SDCCHs

2 Available SDCCHs

3 Configured TCHs

4 Available TCHs

5 Available SDCCH rate

6 Available TCH rate

Configured SDCCHs Description: This item provides the real-time number of configured SDCCHs, including

the SDCCH converted from the dynamic TCH. It is an average of configured SDCCHs obtained in a sample measurement period.




Measurment point: the system acquires the number of configured SDCCHs every five seconds. By the end of the measurement period, the system devides the sum of all sample data obtained in the period by sampling times to calculate the average configured SDCCHs measured in the measurment period.

Formula: none.

Available SDCCHs Description: This item provides the number of available SDCCHs (including the

SDCCH converted from the dynamic TCH) which are in idle or busy status in the BSC system. It is an average number of available SDCCHs obtained in a sample measurement period.

Measurement point: the system acquires the number of available SDCCHs every five seconds. By the end of the measurement period, the system devides the sum of all sample data obtained in the period by sampling times to calculate the average available SDCCHs measured in the measurment period.

Formula: none.

Configured TCHs Description: This item provides the real-time number of configured TCHs (besides the

dynamical TCHs converted into SDCCHs but includes the TCHs converted from dynamic PDCHs). It is an average of configured TCHs obtained in a sample measurement period.

Measurement point: the system acquires the number of configured TCHs every five seconds. By the end of the measurement period, the system devides the sum of all sample data obtained in the period by sampling times to calculate the average configured TCHs measured in the measurment period.

Formula: none.

Available TCHs Description: This item provides the number of available TCHs (besides the dynamical

TCHs converted into SDCCHs but includes the TCHs converted from dynamic PDCHs) which are in idle or busy status in the BSC system. It is an average number of available TCHs obtained in a sample measurement period.

Measurement point: the system acquires the number of available TCHs every five seconds. By the end of the measurement period, the system devides the sum of all sample data obtained in the period by sampling times to calculate the average available TCHs measured in the measurment period.

Formula:none.

Available SDCCH rate Description: This item provides the percentage (%) of available SDCCHs to configured

SDCCHs. See Available SDCCHs, Configured SDCCHs. Measurement point: none. Formula: Available SDCCHs/Configured SDCCHs

Available TCH rate Description: This item provides the percentage (%) of available TCHs to configured

TCHs. See Available TCHs,. Configured SDCCHs



Measurement point: none. Formula: Available TCHs/Configured TCHs

3.1.4 Handover Measurement Function(1) All the statistic items of Handover Measurement Function(1) are listed in Table 3-3.

Table 3-3 Statistic items in Handover measurement function(1) items

No. Item name

1 Attempted Intracell Handovers

2 Successful Intracell Handovers

3 Unsuccessful Intracell Handovers,

4 Attempted Intercell Handovers

5 Intercell Handovers

6 Attempted Intercell Handovers (900/850(1800/1900)

7 Attempted Intercell Handovers (1800/1900(900/850)

8 Successful Intercell Handovers

9 Successful Intercell Handovers (900/850(1800/1900)

10 Successful Intercell Handovers (1800/1900(900/850)

11 Intra BSC Handovers

12 Attempted Incoming BSC Handovers

13 Attempted Incoming BSC Handovers (900/850(1800/1900)

14 Attempted Incoming BSC Handovers (1800/1900(900/850)

15 Attempted Incoming BSC Handovers (to 900/850)

16 Attempted Incoming BSC Handovers (to 1800/1900)

17 Successful Incoming BSC Handovers

18 Successful Incoming BSC Handovers (900/850(1800/1900)

19 Successful Incoming BSC Handovers (1800/1900(900/850)

20 Successful Incoming BSC Handovers (to 900/850)

21 Successful Incoming BSC Handovers (to 1800/1900)

22 Unsuccessful Incoming BSC Handovers

23 Unsuccessful Incoming BSC Handovers (Equipment Failure)

24 Unsuccessful Incoming BSC Handovers (Requested Terrestrial Resource Unavailable)

25 Unsuccessful Incoming BSC Handovers (Terrestrial Circuit Already Allocated)




No. Item name

26 Unsuccessful Incoming BSC Handovers (Invalid Message Contents)

27 Unsuccessful Incoming BSC Handovers (No Radio Resource Available)

28 Unsuccessful Incoming BSC Handovers (Other Causes)

29 Unsuccessful Channel Activation in Incoming BSC Handovers (NACK)

30 Channel Activation Timeout in Incoming BSC Handovers

31 Incoming BSC Handovers

32 Attempted Outgoing BSC Handovers

33 Attempted Outgoing BSC Handovers (from 900/850)

34 Attempted Outgoing BSC Handovers (from 1800/1900)

35 Attempted Outgoing BSC Handovers (900/850(1800/1900)

36 Attempted Outgoing BSC Handovers (1800/1900(900/850)

37 Successful Outgoing BSC Handovers

38 Successful Outgoing BSC Handovers (from 900/850)

39 Successful Outgoing BSC Handovers (from 1800/1900)

40 Successful Outgoing BSC Handovers (900/850(1800/1900)

41 Successful Outgoing BSC Handovers (1800/1900(900/850)

42 Outgoing BSC Handovers

43 Unsuccessful Outgoing BSC Handovers with Successful Reversion

44 Unsuccessful Outgoing BSC Handovers with Unsuccessful Reversion

45 Successful BSC Inter-Layer Handovers (Upper To Lower)

46 Successful BSC inter-Layer Handovers (Lower To Upper)

47 Unsuccessful BSC Internal Handovers With Successful reversion

48 Unsuccessful BSC Internal Handovers With Unsuccessful Reversion

49 Attempted handovers (intracell TCHF-TCHH handover)

50 Successful handovers (intracell TCHF-TCHH handover)

51 Attempted Intercell Handovers (from 900/850)

52 Attempted intercell handovers(from 1900/1800)

53 Attempted handovers (intracell TCHF-TCHH handover)

54 Intra BSC inter-cell radio handover success rate

55 Intracell Handover Success Rate

56 Incoming BSC Handover Success Rate



No. Item name

57 Outgoing BSC Handover Success Rate

58 Ratio of Intra-BSC Interband Handover To Total Intrabsc Handover

59 Ratio of Inter BSC Interband Handover to Total Inter BSC Handover

60 Dual-Band Handover Success Rate

61 Intra BSC Radio Handover Success Rate

62 Incoming BSC Radio Handover Success Rate

63 Outgoing BSC Radio Handover Success Rate

Attempted Intracell Handovers Description: Intracell handover is normally triggered by receiving strength, receiving

quality, O&M intervention, IUO, and its source cell and the target cell are the same one. This item measures the times of handover attempts which are initiated by a source cell in intracell handover. The measurement result can be used to observe the frequency of the intracell handover initiated by BSC. Together with Intracell TCHF-TCHH Handover Attempt Times

Meaning: Intracell TCHF-TCHH handover means the handover between the half rate channel to the full rate channel in the same cell. The source cell judges whether to implement the intracell TCHF-TCHH handover based on the RQI of the current calling. The source cell and the target cell are the same one. The index “intracell TCHF-TCHH handover attempt times” is used to count the handover attempt times of the target cell. This index can also be used to know the frequency of the intracell TCHF-TCHH handover. Together with the intracell TCHF-TCHH handover success times and the intracell TCHF-TCHH handover failure times, you can know the intracell TCHF-TCHH handover performance within the BSC.

Measurement point: after judged by the handover algorithm, the source cell sends the message “Intracell TCHF-TCHH Handover” to the target cell. The source call and the target cell implements the measurements at the same time.

Measurement calculation formula: none

Successful Intracell Handovers and Intracell TCHF-TCHH Handover Success Times

Meaning:Intracell TCHF-TCHH handover means the handover between the half rate channel to the full rate channel in the same cell. The source cell judges whether to implement the intracell TCHF-TCHH handover based on the RQI of the current calling. The source cell and the target cell are the same one. The index “intracell TCHF-TCHH handover sucess times” is used to count the times that the MS succeeds in handing over to the target cell. Together with the intracell TCHF-TCHH handover attempt times and the intracell TCHF-TCHH handover failure times, you can know the intracell TCHF-TCHH handover performance within the BSC.

Measurement point: count when the MS succeeds in handing over to the target cell and the BSC sends the message ”HANDOVER PERFORMED” to MSC, as shown in Figure 3-232 A1.

Measurement calculation formula: none.




Figure 3-22 Intracell TCHF-TCHH handover success times

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER COMMAND

A1

(Intracell handover)

HANDOVER PERFORMED

A1: intra-cell TCHF-TCHH handover success times

Unsuccessful Intracell Handovers, Meaning: This item reflects the performance of intracell handover in the BSC. Related

items: Attempted Intercell Handovers, Attempted Incoming BSC Handovers, Attempted Outgoing BSC Handovers.

In intraBSC handover procedure, an idle adjacent cell (if the adjacent and the source cell are in different BMs of the same BSC, the adjacent cell will be treated as an idle cell, because system can't get the using situation of channels in other BM’s cell) has a higher priority to be selected as the target cell. If all the neighbour cells that share the same BM module with the source cell are congested, the handover will not be initiated.If the selected adjacent cell and the source cell are the same one, this item will be measured. But the IUO handover (a special handover that still belongs to intracell handover and occurs between the overlaid and underlaid subcell of an IUO cell) is an exception. If the target subcell is congested, the handover cannot be initiated, and the measurement cannot be carried out.

Measurement point: After handover algorithm decision, the source cell sends an Intercell Handover Request message to the target cell, and this item is measured if the source cell is the same as the target cell.

Formula: none.

Attempted Intercell Handovers Description: Internal intercell handover is normally triggered by receiving strength,

receiving quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell, O&M intervention. The source cell and target cells are different ones in the same BSC. This item measures the times of handover attempts which are initiated by a source cell in internal intercell handover procedure. This item reflects the frequency of BSC initiating internal intercell handovers. This item, together with Successful Intercell Handovers helps the user know the performance of the Internal intercell handover. Related item: Attempted Intercell Handovers, Attempted Incoming BSC Handovers, Attempted Outgoing BSC Handovers.

In intra BSC handover procedure, an idle adjacent cell (if the adjacent and the source cell are in different BMs of the same BSC, the adjacent cell will be treated as an idle cell, because system can't get the using situation of channels in other BM’s cell) has a higher priority to be selected as the target cell. If all the neighbour cells that share the same BM module with the source cell are congested, the handover will not be initiated.

Measurement point: After handover algorithm decision, the source cell sends an Intercell Handover Request message to the target cell, and this item is measured if the source cell and the target cell are not the same cell.

Formula: none.



Intercell Handovers Description: During the procedure of internal intercell handover, after successfully

activating the new channel, the target cell will inform the source cell that the channel is ready. After receiving the information from the target cell, the source cell will send HANDOVER COMMAND to the MS. This item measures the times of this message being sent. This item, together with Attempted Intercell Handovers helps the user observe the situation of handover failure due to abnormality during the procedure of preparing new channel in the target cell, or together with Successful Intercell Handovers know the situation of handover failure due to Um interface abnormality. Related items: Intra BSC Handovers, Incoming BSC Handovers.

Measurement point: During the procedure of internal intercell handover, the source cell sends the HANDOVER COMMAND message. This item is measured in this case, as shown in Figure 3-23 A1.

Formula: none.

Figure 3-23 internal intercell handover

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER COMMAND

A1

(Intercell handover)

HANDOVER PERFORMED

CHANNEL ACTCHAN ACT ACK

A1: internal intercell handover

Attempted Intercell Handovers (900/850d1800/1900) Description: Internal intercell handover is normally triggered by receiving strength,

receiving quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell, O&M intervention. The source cell and target cells are different ones controlled by the same BSC. This item measures the times of handover attempts from the source cell (GSM900/850) to the target cell (GSM1800/1900) in internal intercell handover. This item, together with Attempted Intercell Handovers (1800/1900(900/850), helps the user know the frequency of interband handovers, or together withSuccessful Intercell Handovers (900/850(1800/1900), know the performance of interband handover in the BSC. Related items: Attempted Intercell Handovers.

I intraBSC handover procedure, an idle adjacent cell (if the adjacent and the source cell are in different BMs of the same BSC, the adjacent cell will be treated as an idle cell, because system can't get the using situation of channels in other BM’s cell) has a higher priority to be selected as the target cell. If all the neighbour cells that share the same BM module with the source cell are congested, the handover will not be initiated.

Cell system type: GSM900/850 cell and GSM1800/1900 cell. GSM 900 cell: The frequency value of this cell is in GSM900 band, and the corresponding ARFCN is from 1 to 124 and 995 to 1023.




GSM 1800 cell: The frequency value of this cell is in GSM1800 band, and the corresponding ARFCN is from 512 to 885. PCS1900 cell: the cell frequency belongs to PCS 1900, range: 512–810. GSM850 cell: the cell frequency belongs to GSM 850, range: 128–251.

Measurement point: Measured when the source cell (GSM900/850 cell) sends Intercell Handover Request to the target cell (GSM1800/1900 cell) after handover algorithm decision.

Formula: none.

Attempted Intercell Handovers (1800/1900d900/850) Description: Internal intercell handover is normally triggered by receiving strength,

receiving quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell, O&M intervention. The source cell and target cells are different ones controlled by the same BSC. This item measures the times of handover attempts from the source cell (GSM1800/1900) to the target cell (GSM900/850) in internal intercell handover. This item, together withAttempted Intercell Handovers (900/850(1800/1900), helps the user know the frequency of interband handovers, or together with Successful Intercell Handovers (1800/1900(900/850) to know the performance of interband handover in the BSC. Related items: Attempted Intercell Handovers.

In intraBSC handover, an idle adjacent cell will be selected as the target cell. If all the neighbour cells that share the same BM module with the source cell are congested, the handover will not be initiated.

Cell system type: GSM900/850 cell and GSM1800/1900 cell. GSM 900 cell: The frequency value of this cell is in GSM900 band, and the corresponding ARFCN is from 1 to 124 and 995 to 1023. GSM 1800 cell: The frequency value of this cell is in GSM1800 band, and the corresponding ARFCN is from 512 to 885. PCS1900 cell: the cell frequency belongs to PCS 1900, range: 512–810. GSM850 cell: the cell frequency belongs to GSM 850, range: 128–251.

Measurement point: Measured when the source cell (GSM1800/1900 cell) sends Intercell Handover Request to the target cell (GSM900/850 cell) after handover algorithm decision.

Formula: none.

Successful Intercell Handovers Description: Internal intercell handovers can be classified into two types by the handover

cause: DIRECTED RETRY, non-DIRECTED RETRY (e.g. signal quality, signal strength, TA, traffic load, rapid rxlevel drop, better cell, Response to MSC invocation, and O&M intervention). This item measures the times of successful internal intercell handovers. This item, together with Attempted Intercell Handovers, helps the user know the performance of internal intercell handover. Related items: Intracell TCHF-TCHH Handover Attempt Times

Meaning: Intracell TCHF-TCHH handover means the handover between the half rate channel to the full rate channel in the same cell. The source cell judges whether to implement the intracell TCHF-TCHH handover based on the RQI of the current calling. The source cell and the target cell are the same one. The index “intracell TCHF-TCHH handover attempt times” is used to count the handover attempt times of the target cell. This index can also be used to know the frequency of the intracell TCHF-TCHH handover. Together with the intracell TCHF-TCHH handover success times and the



intracell TCHF-TCHH handover failure times, you can know the intracell TCHF-TCHH handover performance within the BSC.


Measurement calculation formula: none Successful Intracell Handovers, Successful Incoming BSC Handovers and Successful

Outgoing BSC Handovers. Measurement point:

− Measured when BSC sends ASSIGNMENT COMPLETE to MSC after the MS has successfully accessed in the target cell in internal intercell handover procedure (handover cause: DIRECTED RETRY), as shown in Figure 3-24 A1.

− Measured when BSC sends HANDOVER PERFORMED to MSC after the MS has successfully accessed in the target cell in the internal intercell handover procedure (handover cause: non-DIRECTED RETRY, e.g. signal quality, signal strength, TA, traffic load, rapid rxlevel drop, better cell, Response to MSC invocation, and O&M intervention), as shown in Figure 3-24 A1.

Formula: none.

Figure 3-24 Successful internal intercell handover (DIRECTED RETRY)

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER COMMAND

A1

ASSIGNMENT REQUEST

ASSIGNMENT COMPLETE

C1 B1

A1: Successful internal intercell handover B1: Successful internal intercell handover (900/850-1800/1900) C1: Successful internal intercell handover (1800/1900-900/850)




Figure 3-25 Successful Internal intercell handover (not DIRECTED RETRY)

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

.HANDOVER COMMAND

A1

(Intercell Handover)

HANDOVER PERFORMED

C1 B1

A1: Successful Internal intercell handover B1: Successful Internal intercell handover (900/850-1800/1900) C1: Successful Internal intercell handover (1800/1900-900/850)

Successful Intercell Handovers (900/850d1800/1900) Description: Internal intercell handovers can be classified into two types by the handover

cause: DIRECTED RETRY, non-DIRECTED RETRY (e.g. signal quality, signal strength, TA, traffic load, rapid rxlevel drop, better cell, Response to MSC invocation, and O&M intervention). This item measures the times of successful internal intercell handovers from GSM900/850 cell to GSM1800/1900 cell. This item, together with Attempted Intercell Handovers (900/850(1800/1900) helps the user know the performance of interband handover in the BSC. Related items: Successful Intercell Handovers.


Measurement point: − In internal intercell handover (handover cause: DIRECTED RETRY), the source cell

is a GSM900/850 cell and the target cell is a GSM1800/1900 one. After MS successfully accessed the target cell, BSC sends ASSIGNMENT COMPLETE to MSC. This item is measured in this case, as shown in Figure 3-24 B1.

− In internal intercell handover (handover cause: non-DIRECTED RETRY, e.g. signal quality, signal strength, TA, traffic load, rapid rxlevel drop, better cell, Response to MSC invocation, and O&M intervention), the source cell is a GSM900/850 cell and the target cell is a GSM1800/1900 one. After MS successfully handed over to the target cell, BSC sends a HANDOVER PERFORMED message to MSC. This item is measured in this case, as shown in Figure 3-25 B1.

Formula: none.



Successful Intercell Handovers (1800/1900d900/850) Description: Internal intercell handovers can be classified into two types by the handover

cause: DIRECTED RETRY, non-DIRECTED RETRY (e.g. signal quality, signal strength, TA, traffic load, rapid rxlevel drop, better cell, Response to MSC invocation, and O&M intervention). This item measures the times of successful internal intercell handovers from GSM1800/1900 cell to GSM900/850 cell. This item, together with Attempted Intercell Handovers (1800/1900(900/850) to know the performance of inter-frequency handover in the BSC. Related items: Successful Intercell Handovers.


Measurement point: − In an internal intercell handover (handover cause: DIRECTED RETRY), the source

cell is a GSM1800/1900 cell and the target cell is a GSM900/850 one. After MS successfully handed over to the target cell, BSC sends an ASSIGNMENT COMPLETE message to MSC. This item is measured in this case, as shown in Figure 3-24 C1.

− In a Internal intercell handover (handover cause: non-DIRECTED RETRY, e.g. signal quality, signal strength, TA, traffic load, rapid rxlevel drop, better cell, Response to MSC invocation, and O&M intervention), the source cell is a GSM1800/1900 cell and the target cell is a GSM900/850 one. After successfully handed over to the target cell, BSC sends HANDOVER PERFORMED to MSC. This item is measured in this case, as shown in Figure 3-25 C1.

Formula: none.

Intra BSC Handovers Description: There are two types of intraBSC handovers: internal intracell handover and

internal intercell handover. After successfully activating the new channel, the target cell informs the source cell that the channel is ready. After receiving this information, the source cell sends a HANDOVER COMMAND message to MS. This item measures the total times of sending this message in the BSC, both in the cases of intercell handover and intracell handover. This item, together with Intercell Handovers, helps the user know the times of internal intracell handovers. Related items: Intercell Handovers, Incoming BSC Handovers.

Measurement point: During the procedure of intraBSC handover, the source cell sends the HANDOVER COMMAND message. This item is measured in this case, as shown in Figure 3-26 A1.

Formula: none.




Figure 3-26 Intra BSC handover

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

.HANDOVER COMMAND

A1

HANDOVER PERFORMED

CHANNEL ACT

CHAN ACT ACK

A1: Intra BSC handover

Attempted Incoming BSC Handovers Description: During the procedure of inter BSC handover, source BSC initiates a

handover by sending a HANDOVER REQUIRED message to MSC. After receiving this message, MSC sends a HANDOVER REQUEST message to target BSC. The target BSC receives this message, and starts the preparation of new channel. This item measures the times of target BSC receiving handover requests. This item reflects the frequency of the handover from other BSCs to local BSC. Together with Successful Incoming BSC Handovers, this item helps the user know the performance of this type of handover in the local BSC. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers and Attempted Outgoing BSC Handovers.

Measurement point: During the procedure of inter BSC handover, the target BSC receives HANDOVER REQUEST from MSC. This item is measured in this case, as shown in Figure 3-27 F1.

Formula: none.



Figure 3-27 Successful incoming BSC handover

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER DETECTION

A1 ,B1 ,C1 , D1, E1

CHANNEL ACT

CHAN ACT ACK

HANDOVER COMPLETE

HANDOVER REQ ACK

HANDOVER REQUESTF1

A1: Successful incoming BSC handover B1: Successful incoming BSC handover (900/850-1800/1900) C1: Successful incoming BSC handover (1800/1900-900/850) D1: Successful incoming BSC handover (to 900/850) E1: Successful incoming BSC handover (to 1800/1900) F1: Successful incoming BSC handover

Attempted Incoming BSC Handovers (900/850d1800/1900) Description: During the procedure of inter BSC handover, the target BSC receives

HANDOVER REQUEST from MSC, and then packs this message into IntoBSC Handover Request, which will be sent to the BM which the target cell belongs to. This item measures the times of the target BSC receiving IntoBSC Handover Request when the source cell is a GSM900/850 one, and the target cell is a GSM1800/1900 one. This item reflects the frequency of the handover from GSM900/850 cells of other BSCs to GSM1800/1900 cells of the local BSC. Together with Successful Incoming BSC Handovers (900/850(1800/1900), this item helps the user know the performance of this type of handover. Related items: Attempted Incoming BSC Handovers.


Measurement point: During the procedure of inter BSC handover, the BM which the target cell belongs to receives IntoBSC Handover Request, and the source cell is a GSM900/850 one, the target cell is a GSM1800/1900 one. This item is measured in this case.

Formula: none.




Attempted Incoming BSC Handovers (1800/1900d900/850) Description: During the procedure of inter BSC handover, the target BSC receives

HANDOVER REQUEST from MSC, and then packs this message into IntoBSC Handover Request, which will be sent to the BM which the target cell belongs to. This item measures the times of the target BSC receiving IntoBSC Handover Request when the source cell is a GSM1800/1900 one, and the target cell is a GSM900/850 one. This item reflects the frequency of the handover from GSM1800/1900 cells of other BSCs to GSM900/850 cells of the local BSC. Together with Successful Incoming BSC Handovers (1800/1900(900/850), this item helps the user know the performance of this type of handover. Related items: Attempted Incoming BSC Handovers.


Measurement point: During the procedure of inter BSC handover, the BM which the target cell belongs to receives Inter IntoBSC Handover Request, and the source cell is a GSM1800/1900 one, while the target cell is a GSM900/850 one. This item is measured in this case.

Formula: none.

Attempted Incoming BSC Handovers (to 900/850) Description: During the procedure of inter BSC handover, the target BSC receives

HANDOVER REQUEST from MSC, and then packs this message into IntoBSC Handover Request, which will be sent to the BM which the target cell belongs to. This item measures the times of the target BSC receiving the Inter IntoBSC Handover Request message when the target cell is a GSM900/850 one. This item reflects of the handover to GSM900/850 cells of the local BSC. Together with Successful Incoming BSC Handovers (to 900/850), this item helps the user know the performance of this type of handover. Related items: Attempted Incoming BSC Handovers.

Measurement point: During the procedure of inter BSC handover, the BM which the target cell belongs to receives Inter IntoBSC Handover Request, and the target cell is a GSM900/850 one. This item is measured in this case.

Formula: none.

Attempted Incoming BSC Handovers (to 1800/1900) Description: During the procedure of inter BSC handover, the target BSC receives the

HANDOVER REQUEST message from MSC, and then packs this message into the Inter IntoBSC Handover Request message, which will be then sent to the BM which the target cell belongs to. This item measures the times of the target BSC receiving the Inter IntoBSC Handover Request message when the target cell is a GSM1800/1900 one. This item reflects of the handover to GSM1800/1900 cells of the local BSC. Together with Successful Incoming BSC Handovers (to 1800/1900), this item helps the user know the performance of this type of handover. Related items: Attempted Incoming BSC Handovers.

Cell system type: GSM900/850 cell and GSM1800/1900 cell.



GSM 900 cell: The frequency value of this cell is in GSM900 band, and the corresponding ARFCN is from 1 to 124 and 995 to 1023. GSM 1800 cell: The frequency value of this cell is in GSM1800 band, and the corresponding ARFCN is from 512 to 885. PCS1900 cell: the cell frequency belongs to PCS 1900, range: 512–810. GSM850 cell: the cell frequency belongs to GSM 850, range: 128–251.

Measurement point: During the procedure of inter BSC handover, the BM which the target cell belongs to receives Inter IntoBSC Handover Request, and the target cell is a GSM1800/1900 one. This item is measured in this case.

Formula: none.

Successful Incoming BSC Handovers Description: During the procedure of inter BSC handover, the target BSC receives the

HANDOVER REQUEST message from MSC, and starts the preparation of new channel. After the channel preparation has been done, and the MS has accessed the target cell, the target BSC sends a HANDOVER COMPLETE message to MSC to indicate that the handover has finished. This item, together with Attempted Incoming BSC Handovers, helps the user know the performance of this type of handover. Related items: Successful Outgoing BSC Handovers, Successful Intercell Handovers, Intracell TCHF-TCHH Handover Attempt Times



Measurement calculation formula: none Successful Intracell Handovers. Measurement point: During the procedure of inter BSC handover, the target BSC

receives HANDOVER COMPLETE, and forward it to MSC, as shown in Figure 3-27 A1.

Formula: none.

Successful Incoming BSC Handovers (900/850d1800/1900) Description: During the procedure of inter BSC handover, the target BSC receives the

HANDOVER REQUEST message from MSC, and starts the preparation of new channel. After the channel preparation has been done, and the MS has accessed the target cell, the target BSC sends a HANDOVER COMPLETE message to MSC to indicate that the handover has finished. This item measures the successful handovers from other BSCs (GSM900/850 cells) to local BSC (GSM1800/1900 cell). This item, together with Attempted Incoming BSC Handovers (900/850(1800/1900), helps the user know the performance of the handover of this type. Related parameters: Successful Incoming BSC Handovers.





Measurement point: During the procedure of inter BSC handover from GSM900/850 cell to GSM1800/1900 cell, the target BSC receives the HANDOVER COMPLETE message, and forwards it to MSC, as shown in Figure 3-27 B1.

Formula: none.

Successful Incoming BSC Handovers (1800/1900d900/850) Description: During the procedure of inter BSC handover, the target BSC receives the

HANDOVER REQUEST message from MSC, and starts the preparation of new channel. After the channel preparation has been done, and the MS has accessed the target cell, the target BSC sends a HANDOVER COMPLETE message to MSC to indicate that the handover has finished. This item measures the successful handovers from other BSCs (GSM1800/1900 cells) to local BSC (GSM900/850 cell). This item, together with Attempted Incoming BSC Handovers (1800/1900(900/850), helps the user know the performance of the handover of this type. Related parameters: Successful Incoming BSC Handovers.

Measurement point: During the procedure of inter BSC handover from GSM1800/1900 cell to GSM900/850 cell, the target BSC receives the HANDOVER COMPLETE message, and forwards it to MSC, as shown in Figure 3-27 C1.

Formula: none.

Successful Incoming BSC Handovers (to 900/850) Description: During the procedure of inter BSC handover, the target BSC receives the

HANDOVER REQUEST message from MSC, and starts the preparation of new channel. After the channel preparation has been done, and the MS has accessed the target cell, the target BSC sends a HANDOVER COMPLETE message to MSC to indicate that the handover has finished. This item measures the successful handovers from other BSCs to local BSC (GSM900/850 cell). This item, together with Attempted Incoming BSC Handovers (to 900/850), helps the user know the performance of the handover of this type. Related parameters: Successful Incoming BSC Handovers.

Measurement point: During the procedure of inter BSC handover to GSM900/850 cell, the target BSC receives the HANDOVER COMPLETE message, and forwards it to MSC, as shown in Figure 3-27 D1.

Formula: none.

Successful Incoming BSC Handovers (to 1800/1900) Description: During the procedure of inter BSC handover, the target BSC receives the

HANDOVER REQUEST message from MSC, and starts the preparation of new channel. After the channel preparation has been done, and the MS has accessed the target cell, the target BSC sends a HANDOVER COMPLETE message to MSC to indicate that the handover has finished. This item measures the successful handovers from other BSCs to local BSC (GSM1800/1900 cell). This item, together with Attempted Incoming BSC



Handovers (to 1800/1900), helps the user know the performance of the handover of this type. Related parameters: Successful Incoming BSC Handovers.

Measurement point: During the procedure of inter BSC handover to GSM900/850 cell, the target BSC receives the HANDOVER COMPLETE message, and forwards it to MSC, as shown in Figure 3-27 E1.

Formula: none.

Unsuccessful Incoming BSC Handovers Description: During the procedure of inter BSC handover, the target BSC receives

HANDOVER REQUEST from MSC, and then packs this message into IntoBSC Handover Request, and sends the packed message to the BM which the target cell belongs to request internal resource. And then the BSC checks the conditions of incoming BSC handover. If the conditions can be satisfied, the BSC applies for channel resource and generates HANDOVER COMMAND. And then the BSC activates the new channel and waits for the access of an MS on the new channel. On receiving HANDOVER COMPLETE from the MS, the target BSC sends a HANDOVER COMPLETE message to MSC, and this handover is finished here. If abnormality takes place during this period, BSC will send CLEAR REQUEST or HANDOVER FAILURE to MSC to indicate that the BSC wishes to release the associated dedicated resource(s). This means this incoming BSC handover fails. This item, together with Attempted Incoming BSC Handovers helps the user know the performance of this type of handover. The unsuccessful incoming BSC handovers with all kinds of specified cause can help know the details that cause the failure of BSC incoming handover. Related items: Unsuccessful Outgoing BSC Handovers with Successful Reversion and Unsuccessful Outgoing BSC Handovers with Successful Reversion.

The causes of unsuccessful incoming BSC handover can be:

Equipment failure; Resource congestion or resource unavailable; Message content invalid; Timers time out; Error detected during BSS internal processing, e.g. storing a message in buffer failed, No. of target

cell invalid, message decoding failed; MSC informs BSC to clear resources.

Measurement point: − During the procedure of inter BSC handover, the target BSC processes the

HANDOVER REQUEST message. This item is measured if the following abnormalities occur, and in this case, BSC will send a HANDOVER FAILURE message to MSC: message decoding failed, service type is speech or data but no CIC contained or the contained CIC does not belong to the target BSC.

− During the procedure of inter BSC handover, the target BSC obtains the specified CIC which is presented in the HANDOVER REQUEST message. This item is measured when the following abnormalities occur, and in this case, BSC will send a HANDOVER FAILURE message to MSC: the state of the specified CIC is busy or abnormal, mismatching between circuit pool and channel rate type or speech version.

− During the procedure of inter BSC handover, the target BSC sends a HANDOVER FAILURE message to MSC for AM/CM net-drive fails. This item is measured in this case send a HANDOVER FAILURE message to.

− During the procedure of inter BSC handover, the target BSC will check the incoming BSC handover conditions. This item is measured when abnormalities are detected, and BSC will at the same time send a HANDOVER FAILURE message to MSC. The




abnormalities include: Service type is data but the channel rate type is unknown, fail to request channel, ciphering algorithm is not supported.

− During the procedure of inter BSC handover, the target BSC fails to send a CHANNEL ACTIVATION message. This item is measured in this case, and at the same time, BSC sends a HANDOVER FAILURE message to MSC.

− During the procedure of inter BSC handover, the target BSC receives the CHANNEL ACTIVATION NEGATIVE ACKNOWLEDGE message. This item is measured in this case, and at the same time, BSC will send a HANDOVER FAILURE message to MSC, as shown in Figure 3-28 A1.

− During the procedure of inter BSC handover, the target BSC receives CONNECTION FAILURE INDICATION from BTS after receiving HANDOVER DETECTION. . This item is measured in this case, and at the same time, BSC will send a HANDOVER FAILURE message to MSC, as shown in Figure 3-28 A2.

− During the procedure of inter BSC handover, the target BSC receives the HANDOVER DETECTION message or HANDOVER COMPLETE. This item is measured when the decoding of these messages failed, and in this case, BSC will send a CLEAR REQUEST message to MSC.

− During the procedure of inter BSC handover, the target BSC sends a HANDOVER COMPLETE message to MSC. This item is measured when BSC fails to send this message, and in this case, BSC will send a CLEAR REQUEST message to MSC.

− During the procedure of inter BSC handover, the target BSC starts timer waiting for the CHANNEL ACTIVATION ACKNOWLEDGE message. This item is measured when this timer times out, and in this case, BSC will send a HANDOVER FAILURE message to MSC.

− During the procedure of inter BSC handover, the target BSC starts timer Tqho (maximum allowed queuing time for handover). This item is measured when the timer times out, and in this case, BSC will send a HANDOVER FAILURE message to MSC.

− During the procedure of inter BSC handover, the target BSC starts timer waiting for HANDOVER DETECTION or timer waiting for HANDOVER COMPLETE. This item is measured when these timers time out, and in this case, BSC will send a CLEAR REQUEST message to MSC.

− During the procedure of inter BSC handover, the target BSC receives the CLEAR COMMAND message from MSC. This item is measured in this case, as shown in Figure 3-28 A3~A5.

Formula: none.



Figure 3-28 Unsuccessful incoming BSC handover

MS BTS New BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER COMMAND

HANDOVER COMPLETE

CONN FAIL IND

CONN FAIL IND

HANDOVER DETECTION

A1

New Channel

HANDOVER REQUEST

Old BSC

HANDOVER REQUIRED

CHAN ACT

CHAN ACT ACK

CHAN ACT NACK

New Channel

A2

CLEAR COMMAND

CLEAR COMMAND

CLEAR COMMAND

A3

A4

A5

B1

B2

A3 C1

C2

C3

D1

A1~A5 : Unsuccessful incoming BSC handover B1~B2: Unsuccessful incoming BSC handover (equipment failure) C1~C3: Unsuccessful incoming BSC handover (other causes) D1 : Unsuccessful incoming BSC handover (NACK)

Unsuccessful Incoming BSC Handovers (Equipment Failure) Description: This item measures the times of unsuccessful incoming BSC handovers due

to equipment failure during the procedure of inter BSC handover. Related items: Unsuccessful Incoming BSC Handovers.


HANDOVER REQUEST message. This item is measured when service type is speech or data but the contained CIC does not belong to the target BSC, and in this case, BSC will send a HANDOVER FAILURE message to MSC.

− During the procedure of inter BSC handover, the target BSC sends a HANDOVER FAILURE message to MSC for AM/CM net-drive fails. This item is measured in this case, and at the same time, BSC will send a HANDOVER FAILURE message to MSC.

− During the procedure of inter BSC handover, the target BSC will check the incoming BSC handover conditions. This item is measured when abnormalities of equipment failure are detected, and BSC will at the same time send a HANDOVER FAILURE message to MSC.

− During the procedure of inter BSC handover, the target BSC fails to send a CHANNEL ACTIVATION message. This item is measured in this case, and at the same time, BSC sends a HANDOVER FAILURE message to MSC.

− During the procedure of inter BSC handover, when the target BSC receives the CHANNEL ACTIVATION NEGATIVE ACKNOWLEDGE message, this item is measured in this case, and at the same time, BSC will send a HANDOVER FAILURE message to MSC, as shown in Figure 3-28 B1.




− During the procedure of inter BSC handover, the target BSC receives the HANDOVER DETECTION message, and then receives the CONNECTION FAILURE INDICATION message. This item is measured in this case, and at the same time, THE BSC will send a HANDOVER FAILURE message to MSC, as shown in Figure 3-28 B2.

− During the procedure of inter BSC handover, the target BSC starts the timer waiting for the CHANNEL ACTIVATION ACKNOWLEDGE message. This item is measured when this timer times out, and in this case, BSC will send a HANDOVER FAILURE message to MSC.

Formula: none.

Unsuccessful Incoming BSC Handovers (Requested Terrestrial Resource Unavailable)

Description: This item measures the times of unsuccessful incoming BSC handovers due to requested terrestrial resource unavailable during the procedure of inter BSC handover. Related items: Unsuccessful Incoming BSC Handovers.

Measurement point: During the procedure of inter BSC handover, the target BSC obtains the specified CIC in the handover request. This item is measured when the specified CIC is abnormal, and in this case, BSC will send a HANDOVER FAILURE message to MSC.

Formula: none.

Unsuccessful Incoming BSC Handovers (Terrestrial Circuit Already Allocated) Description: This item measures the times of unsuccessful incoming BSC handovers due

to terrestrial circuit already allocated during the procedure of inter BSC handover. Related items: Unsuccessful Incoming BSC Handovers.

Measurement point: During the procedure of inter BSC handover, the target BSC obtains the specified CIC in the handover request. This item is measured when the specified CIC is busy, and in this case, BSC will send a HANDOVER FAILURE message to MSC.

Formula: none.

Unsuccessful Incoming BSC Handovers (Invalid Message Contents) Description: This item measures the times of unsuccessful incoming BSC handovers due

to invalid message contents during the procedure of inter BSC handover. Related items: Unsuccessful Incoming BSC Handovers.

Measurement point: During the procedure of inter BSC handover, the target BSC will check the incoming BSC handover conditions. This item is measured when service type is data but the channel rate type is unknown, and BSC will at the same time send a HANDOVER FAILURE message to MSC.

Formula: none.

Unsuccessful Incoming BSC Handovers (No Radio Resource Available) Description: This item measures the times of unsuccessful incoming BSC handovers due

to no radio resource available during the procedure of inter BSC handover. Related items: Unsuccessful Incoming BSC Handovers.

Measurement point: − During the procedure of inter BSC handover, the target BSC will check the incoming

BSC handover conditions. This item is measured when there is no channel available,



and BSC will at the same time send a HANDOVER FAILURE message to MSC. For example, requesting for channel failed.

− During the procedure of inter BSC handover, the target BSC starts the timer Tqho (maximum allowed queuing time for handover). This item is measured when this timer times out, and in this case, BSC will send a HANDOVER FAILURE message to MSC.

Formula: none.

Unsuccessful Incoming BSC Handovers (Other Causes) Description: This item measures the times of unsuccessful incoming BSC handovers due

to other causes rather than equipment failure, requested terrestrial resource unavailable, terrestrial circuit already allocated, invalid message contents and no radio resource available during the procedure of inter BSC handover. These causes include sending message failed, timeout of timer waiting for HANDOVER DETECTION or timer waiting for the HANDOVER COMPLETE message. Related items: Unsuccessful Incoming BSC Handovers.


HANDOVER REQUEST message. This item is measured if the following abnormalities occur, and in this case, BSC will send a HANDOVER FAILURE message to MSC: message decoding failed, service type is speech or data but no CIC contained.

− During the procedure of inter BSC handover, the target BSC obtains the specified CIC in the handover request. This item is measured when the following abnormalities occur, and in this case, BSC will send a HANDOVER FAILURE message to MSC: mismatching between circuit pool and channel rate type or voice version.

− During the procedure of inter BSC handover, the target BSC will check the incoming BSC handover conditions. This item is measured when abnormalities are detected, and BSC will at the same time send a HANDOVER FAILURE message to MSC. The abnormalities include ciphering algorithm not supported.

− During the procedure of inter BSC handover, the target BSC receives the HANDOVER DETECTION message or the HANDOVER COMPLETE message. This item is measured when the decoding of this message failed, and in this case, BSC will send a CLEAR REQUEST message to MSC.

− During the procedure of inter BSC handover, the target BSC sends a HANDOVER COMPLETE message to MSC. This item is measured when BSC fails to send this message, and in this case, BSC will send a CLEAR REQUEST message to MSC.

− During the procedure of inter BSC handover, the target BSC starts the timer waiting for HANDOVER DETECTION or HANDOVER COMPLETE. This item is measured when this timer times out, and in this case, BSC will send a CLEAR REQUEST message to MSC.

− During the procedure of inter BSC handover, the target BSC receives CLEAR COMMAND from MSC. This item is measured in this case, as shown in Figure 3-28 C1-C3.

Formula: none.

Unsuccessful Channel Activation in Incoming BSC Handovers (NACK) Description: This item measures the times of unsuccessful incoming handovers due to

unsuccessful channel activation in incoming BSC handovers (CHANNEL ACTIVATION NEGATIVE ACKNOWLEDGE received) which is a kind of equipment failure. Related




items: Unsuccessful Incoming BSC Handovers and Unsuccessful Incoming BSC Handovers (Equipment Failure)).

Measurement point: This item is measured when the target BSC that is waiting for the CHANNEL ACTIVATION ACKNOWLEDGE message receives the CHANNEL ACTIVATION NEGATIVE ACKNOWLEDGE message during the procedure of inter BSC handover. In this case, BSC will send a HANDOVER FAILURE message to MSC, as shown in Figure 3-28 D1.

Formula: none.

Channel Activation Timeout in Incoming BSC Handovers Description: This item measures the times of unsuccessful incoming handovers due to

timeout of timer for waiting for the CHANNEL ACTIVATION ACKNOWLEDGE message which is a kind of equipment failure. Related items: Unsuccessful Incoming BSC Handovers and Unsuccessful Incoming BSC Handovers (Equipment Failure).

Measurement point: This item is measured when timer waiting for the CHANNEL ACTIVATION ACKNOWLEDGE message times out in the target BSC, and the BSC will at the same time send a HANDOVER FAILURE message to MSC.

Formula: none.

Incoming BSC Handovers Description: After the target BSC receives the HANDOVER REQUEST message from

MSC, it checks the conditions of incoming handover. If the check passes, the target BSC will request channel resource, generate and store the HANDOVER COMMAND message in buffer, and at the same time, it will send CHANNEL ACTIVATION to BTS. After receiving CHANNEL ACTIVATION ACKNOWLEDGE, the BSC packs the HANDOVER COMMAND message into HANDOVER REQUEST ACKNOWLEDGE, which will then be sent to MSC. MSC transfers this message to the source BSC, and the source BSC sends the HANDOVER COMMAND message to MS. This item measures the times of target BSC sending HANDOVER REQUEST ACKNOWLEDGE to MSC. This item, together with Attempted Incoming BSC Handovers, helps the user know the unsuccessful handovers due to abnormalities during the preparation of new channel in target cell, together with Successful Incoming BSC Handovers, know unsuccessful handovers due to radio interface abnormal. Related items: Intercell Handovers and Intra BSC Handovers.

Measurement point: During the procedure of inter BSC handover, the target BSC receives the CHANNEL ACTIVATION ACKNOWLEDGE message, and then sends to MSC the HANDOVER REQUEST ACKNOWLEDGE message which contains the HANDOVER COMMAND message, a message to be sent to MS. This item is measured in this case, as shown in Figure 3-29 A1.

Formula: none.



Figure 3-29 Incoming BSC handover

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER DETECTION

CHANNEL ACT

CHAN ACT ACK

HANDOVER COMPLETE

HANDOVER REQ ACKA1

A1: Incoming BSC handover

Attempted Outgoing BSC Handovers Description: Inter BSC handover is normally triggered by receiving strength, receiving

quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell or O&M intervention. The source cell and target cell are from different BSCs. The source BSC sends HANDOVER REQUIRED to MSC to initiate a handover. This message contains a list of candidate cells for handover. At this stage, the source BSC does not know the target cell which is selected by MSC or whether the selected cell is congested. It only records the first cell in the candidate list as the default target cell. This item measures the times of source BSC notifying MSC to initiate handover attempts. This item reflects the frequency of local BSC initiating inter BSC handover. Together with Successful Outgoing BSC Handovers, this item shows the performance of the local BSC initiating inter BSC handover. Related items: Attempted Incoming BSC Handovers, Attempted Intercell Handovers and Attempted Intracell Handovers.

Measurement point: After handover algorithm decision, the source BSC sends HANDOVER REQUIRED to MSC. This item is measured in this case, as shown in Figure 3-30 A1.

Formula: none.




Figure 3-30 Attempted outgoing BSC handover

MS BSC2BSC1 MSC/VLR

HANDOVER REQUIREDHANDOVER REQUEST

HANDOVER REQ ACK

HANDOVER COMMAND

HANDOVER COMMANDHANDOVER DETECT

HANDOVER COMPLETE

CLEAR COMPLETE

A1, B1, C1

CLEAR COMMAND

D1, E1, F1

A1: Attempted Outgoing BSC Handovers B1: Attempted Outgoing BSC Handovers (from 900/850) C1: Attempted Outgoing BSC Handovers (from 1800/1900)) D1: Outgoing BSC Handovers E1: Attempted Outgoing BSC Handovers (900/850-1800/1900) F1: Attempted Outgoing BSC Handovers (1800/1900-900/850)

Attempted Outgoing BSC Handovers (from 900/850) Description: Inter BSC handover is normally triggered by receiving strength, receiving

quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell or O&M intervention. The source cell and target cell are from different BSCs. The source BSC sends HANDOVER REQUIRED to MSC to initiate a handover. This message contains a list of candidate cells for handover. At this stage, the source BSC does not know the target cell which is selected by MSC or whether the selected cell is congested. It only knows the source cell (GSM900/850) that initiates this handover. This item measures the times of source BSC (the source cell is GSM900/850 cell) notifying MSC to initiate handover attempts. This item reflects the frequency of GSM900/850 cells of objective BSC initiating inter BSC handover. Together withSuccessful Outgoing BSC Handovers (from 900/850), this item shows the performance of this type handover. Related items: Attempted Outgoing BSC Handovers.


Measurement point: After handover algorithm decision, the source BSC (the source cell is GSM900/850 cell) sends HANDOVER REQUIRED to MSC. This item is measured in this case, as shown in Figure 3-30 B1.



Formula: none.

Attempted Outgoing BSC Handovers (from 1800/1900) Description: Inter BSC handover is normally triggered by receiving strength, receiving

quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell or O&M intervention. The source cell and target cell are from different BSCs. The source BSC sends HANDOVER REQUIRED to MSC to initiate a handover. This message contains a list of candidate cells for handover. At this stage, the source BSC does not know the target cell which is selected by MSC or whether the selected cell is congested. It only knows the source cell (GSM1800/1900) that initiates this handover. This item measures the times of source BSC (the source cell is GSM1800/1900 cell) notifying MSC to initiate handover attempts. This item reflects the frequency of GSM1800/1900 cells of local BSC initiating inter BSC handover. Together with Successful Outgoing BSC Handovers (from 1800/1900), this item shows the performance of this type handover. Related items: Attempted Outgoing BSC Handovers.


Measurement point: After handover algorithm decision, the source BSC (the source cell is GSM900/850 cell) sends HANDOVER REQUIRED to MSC. This item is measured in this case, as shown in Figure 3-30 C1.

Formula: none.

Attempted Outgoing BSC Handovers (900/850d1800/1900) Description: Inter BSC handover is normally triggered by receiving strength, receiving

quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell or O&M intervention. The source cell and target cell are from different BSCs. This item reflects the frequency of local BSC initiating inter BSC handover from GSM900/850 cell to GSM1800/1900 cell. Together with Successful Outgoing BSC Handovers (900/850(1800/1900), this item shows the performance of this type handover. Related items: Attempted Outgoing BSC Handovers.

Te source BSC sends HANDOVER REQUIRED to MSC to initiate handover. This message contains a list of candidate cells for handover. At this stage, the source BSC does not know the target cell which is selected by MSC or whether the selected cell is congested. It only knows the source cell (GSM900/850) that initiates this handover. If the item is measured at this moment, the result is not precise. The target cell and its system type can only be known after receiving the first response message HANDOVER COMMAND from MSC.

Cell system type: GSM900/850 cell and GSM1800/1900 cell. GSM 900 cell: The frequency value of this cell is in GSM900 band, and the corresponding ARFCN is from 1 to 124 and 995 to 1023. GSM 1800 cell: The frequency value of this cell is in GSM1800 band, and the corresponding ARFCN is from 512 to 885. PCS1900 cell: the cell frequency belongs to PCS1900, range: 512–810. GSM850 cell: the cell frequency belongs to GSM850, range: 128–251.




Measurement point: During the procedure of inter BSC handover from GSM900/850 cell to GSM1800/1900 cell, the source BSC receives the HANDOVER COMMAND message from MSC. This item is measured in this case, as shown in Figure 3-30 E1.

Formula: none.

Attempted Outgoing BSC Handovers (1800/1900d900/850) Description: Inter BSC handover is normally triggered by receiving strength, receiving

quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell or O&M intervention. The source cell and target cell are in different BSCs. This item reflects the frequency of local BSC initiating inter BSC handover from GSM1800/1900 cell to GSM900/850 cell. Together with Successful Outgoing BSC Handovers (1800/1900(900/850), this item shows the performance of this type handover. Related items: Attempted Outgoing BSC Handovers.

The source BSC sends HANDOVER REQUIRED to MSC to initiate handover. This message

contains a list of candidate cells for handover. At this stage, the source BSC does not know the target cell which is selected by MSC or whether the selected cell is congested. It only knows the source cell (GSM1800/1900) that initiates this handover. If the item is measured at this moment, the result is not precise. The target cell and its system type can only be known after receiving the first response message HANDOVER COMMAND from MSC.


Measurement point: During the procedure of inter BSC handover from GSM1800/1900 cell to GSM900/850 cell, the source BSC receives the HANDOVER COMMAND message from MSC. This item is measured in this case, as shown in Figure 3-30 F1.

Formula: none.

Successful Outgoing BSC Handovers Description: During the procedure of inter BSC handover, the source BSC sends a

HANDOVER COMMAND message to MS. After successfully accessed the target cell, MSC sends CLEAR COMMAND (cause: handover success) to source BSC to clear the previous resources. This handover successfully ends here. Together withAttempted Outgoing BSC Handovers, this item shows the performance of this type handover. Related items: Intracell TCHF-TCHH Handover Attempt Times





Measurement calculation formula: none Successful Intracell Handovers, Successful Intercell Handovers and Successful Incoming

BSC Handovers. Measurement point: During the procedure of inter BSC handover, the source BSC

receives CLEAR COMMAND (cause: handover success) from MSC. This item is measured in this case, as shown in Figure 3-31 A1.

Formula: none.

Figure 3-31 Successful outgoing BSC handover

MS BSC2BSC1 MSC/VLR

HANDOVER REQUIREDHANDOVER REQUEST

HANDOVER REQ ACK

HANDOVER COMMAND

HANDOVER COMMANDHANDOVER DETECT

HANDOVER COMPLETE

CLEAR COMPLETEA1, B1, C1 , D1, E1

CLEAR COMMAND

A1: Successful outgoing BSC handover B1: Successful outgoing BSC handover (from 900/850) C1: Successful outgoing BSC handover (from 1800/1900)) D1: Successful outgoing BSC handover (900/850-1800/1900) E1: Successful outgoing BSC handover (1800/1900-900/850)

Successful Outgoing BSC Handovers (from 900/850) Description: During the procedure of inter BSC handover, the source BSC sends a

HANDOVER COMMAND message to MS. After successfully accessed the target cell, MS sends CLEAR COMMAND (cause: handover success) to source BSC to clear the previous resources. This handover successfully ends here. This item measures the times of successful outgoing handover originated from GSM900/850 cell. Together with Attempted Outgoing BSC Handovers (from 900/850), this item shows the performance of this type handover. Related items: Successful Outgoing BSC Handovers.





Measurement point: During the procedure of inter BSC handover, the source BSC (source cell is GSM900/850 cell) receives CLEAR COMMAND (cause: handover success) from MSC. This item is measured in this case, as shown in Figure 3-31 B1.

Formula: none.

Successful Outgoing BSC Handovers (from 1800/1900) Description: During the procedure of inter BSC handover, the source BSC sends a

HANDOVER COMMAND message to MS. After successfully accessed the target cell, MS sends CLEAR COMMAND (cause: handover success) to source BSC to clear the previous resources. This handover successfully ends here. This item measures the times of successful outgoing handover originated from GSM1800/1900 cell. Together with Attempted Outgoing BSC Handovers (from 1800/1900), this item shows the performance of this type handover. Related items: Successful Outgoing BSC Handovers.

Measurement point: During the procedure of inter BSC handover, the source BSC (source cell is GSM1800/1900 cell) receives CLEAR COMMAND (cause: handover success) from MSC. This item is measured in this case, as shown in Figure 3-31 C1.

Formula: none.

Successful Outgoing BSC Handovers (900/850d1800/1900) Description: During the procedure of inter BSC handover, the source BSC sends a

HANDOVER COMMAND message to MS. After successfully accessed the target cell, MS sends CLEAR COMMAND (cause: handover success) to source BSC to clear the previous resources. This handover successfully ends here. This item measures the times of successful outgoing handover from GSM900/850 cell to GSM1800/1900 cell. Together with Attempted Outgoing BSC Handovers (900/850(1800/1900), this item shows the performance of this type handover. Related items: Successful Outgoing BSC Handovers.


Measurement point: During the procedure of inter BSC handover from GSM900/850 cell to GSM1800/1900 cell, the source BSC receives CLEAR COMMAND (cause: handover success) from MSC. This item is measured in this case, as shown in Figure 3-31 D1.

Formula: none.

Successful Outgoing BSC Handovers (1800/1900d900/850) Description: During the procedure of inter BSC handover, the source BSC sends a

HANDOVER COMMAND message to MS. After successfully accessed the target cell, MS sends CLEAR COMMAND (cause: handover success) to source BSC to clear the previous resources. This handover successfully ends here. This item measures the times of successful outgoing handover from GSM1800/1900 cell to GSM900/850 cell. Together with Attempted Outgoing BSC Handovers (1800/1900(900/850), this item shows the performance of this type handover. Related items: Successful Outgoing BSC Handovers.




Measurement point: During the procedure of inter BSC handover from GSM1800/1900 cell to GAM900/850 cell, the source BSC receives CLEAR COMMAND (cause: handover success) from MSC. This item is measured in this case, as shown in Figure 3-31 E1.

Formula: none.

Outgoing BSC Handovers Description: During the procedure of inter BSC handover, the target BSC finishes

allocating the new channel and generates the message HANDOVER COMMAND, which is forwarded by MSC to the source BSC. After receiving this message, the source BSC sends it to MS. This item measures the times of the source BSC sending HANDOVER COMMAND. Together with Attempted Outgoing BSC Handovers, this item shows the situation of unsuccessful handovers due to abnormalities in the procedure of new channel preparation, and with Successful Outgoing BSC Handovers, it shows the situation of unsuccessful handovers due to radio interface abnormal. Related items: Incoming BSC Handovers, Intra BSC Handovers and Intercell Handovers.

Measurement point: This item is measured when the source BSC receives HANDOVER COMMAND from MSC, as shown in Figure 3-31 D1.

Formula: none.

Unsuccessful Outgoing BSC Handovers with Successful Reversion Description: During the procedure of inter BSC handover, the source BSC sends a

HANDOVER COMMAND message to MS. If the MS cannot access the target cell due to poor radio environment or handover parameter incorrect, it will send HANDOVER FAILURE (cause: Radio interface failure, reversion to old channel) to the source BSC via the previous channel. BSC then forwards this message to MSC. MSC requests the target BSC to clear the involved resources. The connecting between the source BSC and MS remains the same. This item measures the times of unsuccessful handover with successful reversion. Related items: Unsuccessful Incoming BSC Handovers, Unsuccessful Outgoing BSC Handovers with Unsuccessful Reversion and Unsuccessful BSC Internal Handovers With Successful reversion.

Measurement point: This item is measured when the source BSC receives HANDOVER FAILURE (cause: Radio interface failure, reversion to old channel) from MS during the procedure of inter BSC handover, as shown in Figure 3-32 A1.

Formula: none.




Figure 3-32 Unsuccessful outgoing BSC handovers

B T S B S C 1 M S C / V L R

H A N D O V E R R E Q U I R E D

H A N D O V E R C O M M A N D

C L E A R C O M M A N DC L E A R C O M P L E T E

A 1 H A N D O V E R F A I L U R E

H A N D O V E R F A I L U R E

C L E A R C O M M A N D

C O N N F A I L I N D

E R R O R I N D I C A T I O N

H A N D O V E R C O M M A N D

B 1 B 2

B 3

A1: Unsuccessful outgoing BSC handovers with successful reversion B1: Unsuccessful outgoing BSC handovers with unsuccessful reversion

Unsuccessful Outgoing BSC Handovers with Unsuccessful Reversion Description: During the procedure of inter BSC handover, after the source BSC sends the

HANDOVER COMMAND message to MS, the connection between MS and the source BSC is terminated before the connection established between MS and the target BSC due to poor radio environment or equipment failure. When BSC detects this situation, it will send a CLEAR REQUEST message to MSC to request release the previous resources and the involved resources during handover. This handover failed and the original service cannot be restored in the source BSC. This item measures the times of unsuccessful handover with unsuccessful reversion. Related items: Unsuccessful Incoming BSC Handovers, Unsuccessful Outgoing BSC Handovers with Successful Reversion and Unsuccessful Outgoing BSC Handovers with Unsuccessful Reversion.

Measurement point: − This item is measured when the source BSC receives CLEAR COMMAND (cause:

not handover success) from MSC during the procedure of inter BSC handover, as shown in Figure 3-32 B1.

− This item is measured when the source BSC waiting for CLEAR COMMAND (cause: handover success) from MSC times out during the procedure of inter BSC handover.

Formula: none.

Successful BSC Inter-Layer Handovers (Upper To Lower) Description: This item measures the times of successful internal intercell handovers in

which the layer of the source cell is higher than the layer of the target cell. Related items: Successful BSC inter-Layer Handovers (Lower To Upper) and Successful Intercell Handovers.

The layers of cells are divided into four types, labeled with layer 1~4: 1. Pico, 2. Micro, 3. Macro, 4. Umbrella. The higher layer has the lower priority. The upper layer normally refer to the one with the lower priority between two layers, and the lower layer refers to the one with higher priority. This item aims at the priority among the different type of layers, not at the different priority in the same type of layer.



Measurement point: In internal intercell handover, after MS has been successfully handed over to the target cell, the target cell sends Inter Clear Request to the source cell to instruct the source cell to clear the involved resources. This item is measured when the source cell receives this message, and the layer of the source cell is higher than that of the target cell.

Formula: none.

Successful BSC inter-Layer Handovers (Lower To Upper) Description: This item measures the times of successful BSC internal intercell handovers

in which the layer of the source cell is lower than the layer of the target cell. Related items: Successful BSC Inter-Layer Handovers (Upper To Lower) and Successful Intercell Handovers.

The layers of cells are divided into four types, labeled with layer 1~4: 1. Pico, 2. Micro, 3. Macro, 4. Umbrella. The higher layer has the lower priority. The upper layer normally refers to the one with the lower priority between two layers, and the lower layer refers to the one with higher priority. This item aims at the priority among the different type of layers, not at the different priority in the same type of layer.

Measurement point: In the internal intercell handover, after MS is successfully handed over to the target cell, the target cell sends Inter Clear Request to the source cell to instruct the source cell to clear the involved resources. This item is measured when the source receives this message, and the layer of the source cell is lower than that of the target cell.

Formula: none.

Unsuccessful BSC Internal Handovers With Successful reversion Description: During the procedure of intraBSC handover, the source cell sends a

HANDOVER COMMAND message to MS. If the MS cannot be handed over to the target cell due to poor radio environment or handover parameter incorrect, it will send HANDOVER FAILURE (cause: Radio interface failure, reversion to old channel) to the BSC via the previous channel. On receipt of this message the BSC will release the involved resources associated with the target cell, and the connecting between the BSC and MS remains the same. This item measures the times of unsuccessful handover with successful reversion. Related items: Intracell TCHF-TCHH Handover Success Times








MS BTS BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER COMMAND

A1


HANDOVER PERFORMED


Unsuccessful Intracell Handovers, Unsuccessful Outgoing BSC Handovers with Successful Reversion and Unsuccessful Outgoing BSC Handovers with Unsuccessful Reversion.

Measurement point: This item is measured when the source cell receives HANDOVER FAILURE (cause: Radio interface failure, reversion to old channel) from MS during the procedure of internal intracell handover or internal intercell handover, as shown in Figure 3-32 A1.

Formula: none.

Figure 3-34 Unsuccessful BSC internal handovers

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

.HANDOVER COMMAND

B1

HANDOVER PERFORMED

Old Channel

CONN FAIL INDHANDOVER FAILURE

A1

Old Channel

New Channel

ERROR INDB2

A1: Unsuccessful BSC internal handovers with successful reversion

Unsuccessful BSC Internal Handovers With Unsuccessful Reversion Description: During the procedure of intraBSC handover, after the source BSC sends the

HANDOVER COMMAND message to MS, the connection between MS and the source cell is terminated before the connection between MS and the target cell set up due to poor radio environment or equipment failure. When BSC detects this situation, it will send a CLEAR REQUEST message to MSC to clear the previous resources and the involved resources during handover. This handover failed and the original service cannot



be restored. This item measures the times of unsuccessful handover with unsuccessful reversion. Related items: Intracell TCHF-TCHH Handover Success Times





MS BTS BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER COMMAND

A1


HANDOVER PERFORMED


Unsuccessful Intracell Handovers, Unsuccessful BSC Internal Handovers With Successful reversion and Unsuccessful Outgoing BSC Handovers with Unsuccessful Reversion.

Measurement point: During the procedure of intraBSC handover, the source cell starts the timer waiting for Inter Clear Request after sending HANDOVER COMMAND to MS, this item is measured when the timer times out.

Formula: none.

Attempted handovers (intracell TCHF-TCHH handover) Meaning: intracell TCHF-TCHH hanover means the hanover form full rate channel to

half rate channel or from half rate channel to full rate channel within the same cell. The source cell determines whether to initiate the intracell TCHF-TCHH handover according to the RQI of the current call. The source cell and the target cell are the same. This item measures the attempted handovers initiated by the source cell. The results of this statistic item can reflect the frequency of the intracell TCHF-TCHH handover initiated by local BSC. Together with the two items successful intracell TCHF-TCHH handover and the failed intracell TCHF-TCHH handover, you can know the intracell TCHF-TCHH handover performance in the local BSC.

Measurement point: This item is measured after the source cell sends the Intracell TCHF-TCHH Handover to the target cell. The measurements in the source cell and the target begin at the same time.




Formula: None.

Successful handovers (intracell TCHF-TCHH handover) Meaning: intracell TCHF-TCHH hanover means the hanover form full rate channel to

half rate channel or from half rate channel to full rate channel within the same cell. The source cell determines whether to initiate the intracell TCHF-TCHH handover according to the RQI of the current call. The source cell and the target cell are the same. This item measures the successful handovers. Together with the two items attempted intracell TCHF-TCHH handover and failed intracell TCHF-TCHH handover, you can know the intracell TCHF-TCHH handover performance in the BSC.

Measurement point: This item is measured when the BSC sends the HANDOVER PERFORMED to MSC after the MS hands over to target cell.

Formula: None.

Attempted Intercell Handovers (from 900/850) Description: The BSC intercell handover is triggered by the receiving strength, receiving

quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell, and O&M intervention. The source cell and target cells are different ones in the same BSC. This item measures the times of handover attempts which are initiated by a source cell in internal intercell handover procedure. This item reflects the frequency of the BSC internal intercell handovers from the 900/850 source cell. This item, together with Successful Intercell Handovers helps the user know the performance of the Internal intercell handover. Related item: Attempted Intracell Handovers, Attempted Incoming BSC Handovers and Attempted Outgoing BSC Handovers.

In intra-BSC handover procedure, an idle adjacent cell (if the adjacent and the source cell are in different BMs of the same BSC, the adjacent cell will be treated as an idle cell, because system can't get the using situation of channels in other BM's cell) has a higher priority to be selected as the target cell. If all the neighbour cells that share the same BM module with the source cell are congested, the handover will not be initiated. Cell system type: GSM900/850/1800 cell, and PCS1900 cell GSM 900 cell: the frequency value of this cell is in GSM900 band, and the corresponding ARFCN is from 1 to 124 and 995 to 1023. GSM 1800 cell: The frequency value of this cell is in GSM1800 band, and the corresponding ARFCN is from 512 to 885. PCS1900 cell: the cell frequency belongs to PCS 1900, range: 512–810. GSM850 cell: the cell frequency belongs to GSM850, range: 128–251.

Measurement point: After the decision of the handover algorithm, the source cell (GSM900/850) sends the Intercell Handover Request to the target cell. This item is measured in this case.

Formula: none.

Attempted intercell handovers(from 1900/1800) Description: The BSC intercell handover is triggered by receiving strength, receiving

quality, TA, traffic load, Response to MSC invocation, DIRECTED RETRY, rapid rxlevel drop, better cell, and O&M intervention. The source cell and target cells are different ones in the same BSC. This item measures the times of handover attempts which are initiated by a source cell in internal intercell handover procedure. This item reflects the frequency of BSC initiating internal intercell handovers from the 1900/1800 source cell. This item, together with Successful Intercell Handovers helps the user know



the performance of the Internal intercell handover. Related item: Attempted Intracell Handovers, Attempted Incoming BSC Handovers and Attempted Outgoing BSC Handovers.

In intra-BSC handover procedure, an idle adjacent cell (if the adjacent and the source cell are in different BMs of the same BSC, the adjacent cell will be treated as an idle cell, because system can't get the using situation of channels in other BM's cell) has a higher priority to be selected as the target cell. If all the neighbour cells that share the same BM module with the source cell are congested, the handover will not be initiated. Cell system type: GSM900/850/1800 cell, and PCS1900 cell GSM 900 cell: the frequency value of this cell is in GSM900 band, and the corresponding ARFCN is from 1 to 124 and 995 to 1023. GSM 1800 cell: The frequency value of this cell is in GSM1800 band, and the corresponding ARFCN is from 512 to 885. PCS1900 cell: the cell frequency belongs to PCS 1900, range: 512–810. GSM850 cell: the cell frequency belongs to GSM850, range: 128–251.

Measurement point: After the decision of the handover algorithm, the source cell (GSM1900/1800) sends the Intercell Handover Request to the target cell. This item is measured in this case.

Formula: none.

Intracell Handover Success Rate Description: See Intracell TCHF-TCHH Handover Attempt Times Meaning: Intracell TCHF-TCHH handover means the handover between the half rate

channel to the full rate channel in the same cell. The source cell judges whether to implement the intracell TCHF-TCHH handover based on the RQI of the current calling. The source cell and the target cell are the same one. The index “intracell TCHF-TCHH handover attempt times” is used to count the handover attempt times of the target cell. This index can also be used to know the frequency of the intracell TCHF-TCHH handover. Together with the intracell TCHF-TCHH handover success times and the intracell TCHF-TCHH handover failure times, you can know the intracell TCHF-TCHH handover performance within the BSC.


Measurement calculation formula: none Successful Intracell Handovers, Attempted Intracell Handovers Measurement point: none. Formula: Successful intracell handovers / Attempted intracell handovers

Intra BSC inter-cell radio handover success rate Description: See Successful Intercell Handovers and Intercell Handovers. Measurement point: none. Formula: Successful Intercell Handovers/Intercell Handovers

Intercell Handover Success Rate Description: See Successful Intercell Handovers, Attempted Intercell Handovers. Measurement point: none.




Formula: Successful intercell handovers / Attempted intercell handovers

Incoming BSC Handover Success Rate Description: See Successful Incoming BSC Handovers, Attempted Incoming BSC

Handovers. Measurement point: none. Formula: Successful Incoming BSC Handovers / Attempted Incoming BSC Handovers

Outgoing BSC Handover Success Rate Description: See Successful Outgoing BSC Handovers, Attempted Outgoing BSC

Handovers. Measurement point: none. Formula: Successful outgoing BSC handovers / Attempted outgoing BSC handovers

Ratio of Intra-BSC Interband Handover To Total Intrabsc Handover Description: This item measures the percentage of the intraBSC interband handovers in

total internal intercell handovers. See Attempted Intercell Handovers, Attempted Intercell Handovers (900/850(1800/1900), Attempted Intercell Handovers (1800/1900(900/850).

Measurement point: none. Formula: (Attempted intercell handovers (900/850d1800/1900) + Attempted intercell

handovers (1800/1900d900/850)) / Attempted intercell handovers

Ratio of Inter BSC Interband Handover to Total Inter BSC Handover Description: This item measures the percentage of the inter BSC interband handovers in

total inter BSC handovers. See Attempted Incoming BSC Handovers, Attempted Incoming BSC Handovers (900/850(1800/1900), Attempted Incoming BSC Handovers (1800/1900(900/850), Attempted Outgoing BSC Handovers, Attempted Outgoing BSC Handovers (900/850(1800/1900), Attempted Outgoing BSC Handovers (1800/1900(900/850).

Measurement point: none. Formula: (Attempted Incoming BSC Handovers (900/850d1800/1900) + Attempted

Incoming BSC Handovers (1800/1900d900/850) + Attempted outgoing BSC handovers (900/850d1800/1900) + Attempted outgoing BSC handovers (1800/1900d900/850)) / (Attempted Incoming BSC Handovers + Attempted outgoing BSC handovers)

Dual-Band Handover Success Rate Description: The dual-band handover success rate in a BSC, including intraBSC

dual-band handovers and inter BSC dual-band handovers. See Successful Intercell Handovers (900/850(1800/1900), Successful Intercell Handovers (1800/1900(900/850), Attempted Intercell Handovers (1800/1900(900/850), Attempted Intercell Handovers (1800/1900(900/850), Successful Incoming BSC Handovers (900/850(1800/1900), Successful Incoming BSC Handovers (1800/1900(900/850), Attempted Incoming BSC Handovers (900/850(1800/1900), Attempted Incoming BSC Handovers (1800/1900(900/850), Successful Outgoing BSC Handovers (900/850(1800/1900), Successful Outgoing BSC Handovers (1800/1900(900/850), Attempted Outgoing BSC Handovers (900/850(1800/1900), Attempted Outgoing BSC Handovers (1800/1900(900/850).



Measurement point: none. Formula: (Successful intercell handovers (900/850d1800/1900) + Successful intercell

handovers (1800/1900d900/850) + Successful Incoming BSC Handovers (900/850d1800/1900) + Successful Incoming BSC Handovers (1800/1900d900/850) + Successful outgoing BSC handovers (900/850d1800/1900)+ Successful outgoing BSC handovers (1800/1900d900/850)) / (Attempted intercell handovers (900/850d1800/1900) + Attempted intercell handovers (1800/1900d900/850) + Attempted Incoming BSC Handovers (900/850d1800/1900) + Attempted Incoming BSC Handovers (1800/1900d900/850) + Attempted outgoing BSC handovers (900/850d1800/1900) + Attempted outgoing BSC handovers (1800/1900d900/850))

Intra BSC Radio Handover Success Rate Description: See Intracell TCHF-TCHH Handover Attempt Times Meaning: Intracell TCHF-TCHH handover means the handover between the half rate

channel to the full rate channel in the same cell. The source cell judges whether to implement the intracell TCHF-TCHH handover based on the RQI of the current calling. The source cell and the target cell are the same one. The index “intracell TCHF-TCHH handover attempt times” is used to count the handover attempt times of the target cell. This index can also be used to know the frequency of the intracell TCHF-TCHH handover. Together with the intracell TCHF-TCHH handover success times and the intracell TCHF-TCHH handover failure times, you can know the intracell TCHF-TCHH handover performance within the BSC.


Measurement calculation formula: none Successful Intracell Handovers, Successful Intercell Handovers, Intra BSC Handovers. Measurement point: none. Formula: (Successful intracell handovers + Successful intercell handovers) / Intra BSC

handovers

Incoming BSC Radio Handover Success Rate Description: See Successful Incoming BSC Handovers, Incoming BSC Handovers. Measurement point: none. Formula: Successful incoming BSC handovers / Incoming BSC handovers

Outgoing BSC Radio Handover Success Rate Description: See Successful Outgoing BSC Handovers. Measurement point: none. Formula: Successful outgoing BSC handovers / Outgoing BSC handovers

3.1.5 Handover Measurement Function(2) All the statistic items of Handover Measurement Function(2) are listed in Table 3-4.




Table 3-4 Statistic items in Handover measurement function(2) items

No. Item name

1 Attempted Initiating Handovers (Frequency Offset)

2 Attempted Initiating Handovers (Quick PBGT)

3 Attempted Handovers for Uplink Quality

4 Attempted Handovers for Downlink Quality

5 Attempted Handovers for Uplink Strength

6 Attempted Handovers for Downlink Strength

7 Attempted Handovers for Timing Advance

8 Attempted Handovers for Better Cell

8 Attempted Handovers for Traffic Load

10 Attempted Handovers for Rapid Rxlevel Drop

11 Attempted Handovers for Response to MSC Invocation

12 Attempted Handovers for O&M Intervention

13 Attempted Handovers from Underlaid Subcell to Overlaid Subcell

14 Attempted Handovers from Overlaid Subcell to Underlaid Subcell

15 Attempted Handovers for Directed Retry

16 Attempted Handovers for Other Causes

17 Successful Handovers for Uplink Quality

18 Successful Handovers for Downlink Quality

19 Successful Handovers for Uplink Strength

20 Successful Handovers for Downlink Strength

21 Successful Handovers for Timing Advance

22 Successful Handovers for Better Cell

23 Successful Handovers for Traffic Load

24 Successful Handovers for Rapid Rxlevel Drop

25 Successful Handovers for Response to MSC Invocation

26 Successful Handovers for O&M Intervention

27 Successful Handovers from Underlaid Subcell to Overlaid Subcell

28 Successful Handovers from Overlaid Subcell to Underlaid Subcell

29 Successful Initiating Handovers (Frequency Offset)

30 Successful Initiating Handovers (Quick PBGT)



No. Item name

31 Successful Handovers for Directed Retry

32 Successful Handovers for Other Causes

33 Unsuccessful Incoming BSC Handovers (Tme Out)

34 Unsuccessful TCH Seizures(Error Indication)

35 Unsuccessful TCH Seizures(Connection Failure)

36 Unsuccessful TCH Seizures(Release Indication)

37 Unsuccessful TCH Seizures(EMLPP)

38 Unsuccessful TCH Seizures(Internal Clear)

39 Unsuccessful Cell Internal Handovers with Unsuccessful Reversion

40 Attempted Inter-System Outgoing BSC Handovers

41 Inter-System Outgoing BSC Handovers

42 Successful Inter-System Outgoing BSC Handovers

43 Unsuccessful Inter-System Outgoing BSC Handovers with Successful Reversion

44 Unsuccessful Inter-System Outgoing BSC Handovers with Unsuccessful Reversion

45 Inter-System Outgoing BSC handover success rate

46 Inter-System radio Outgoing BSC handover success rate

Attempted Initiating Handovers (Frequency Offset) Description: When the BSC initiates a handover, it receives a Handover Indication

message from the LAPD module. The message carries the handover causes. The number of attempted handovers is calculated according to the various handover causes. This indicator represents the number of attempted iniatiating handovers cuased by frequency offset. The handover involves both the inter-BSC cell handover and the intra-BSC cell handover. This indicator is used to measure how often the handover caused by frequency offset occurs in the BSC. Together with the Successful Attempted Initiating Handovers (frequency offset) indicator, you can know the performance of this handover. For the related indicators, see142673016.5.807017750 , Successful Intracell Handovers and Intracell TCHF-TCHH Handover Success Times, and Attempted Outgoing BSC Handovers

Measurement point: This indicator is measured when the BSC, caused by frequency offset, sends an Intercell Handover Request message in the case of intra-BSC cell handover or a HANDOVER REQUIRED message in the case of inter-BSC cell handover after the handover algorithm is determined.

Formula: None.

Attempted Initiating Handovers (Quick PBGT) Description: When the BSC initiates a handover, it receives a Handover Indication

message from the LAPD module. The message carries the handover causes. The number




of attempted handovers is calculated according to the various handover causes. This indicator represents the number of attempted iniatiating handovers cuased by frequency offset. The handover involves both the inter-BSC cell handover and the intra-BSC cell handover. This indicator is used to measure how often the handover caused by quick PBGT occurs in the BSC. Together with the Successful Attempted Initiating Handovers (quick PBGT) indicator, you can know the performance of this handover. For the related indicators, seeAttempted Intracell Handovers, Successful Intracell Handovers and Intracell TCHF-TCHH Handover Success Times, andOutgoing BSC Handovers

Measurement point: This indicator is measured when the BSC, caused by quick PBGT, sends an Intercell Handover Request message in the case of intra-BSC cell handover or a HANDOVER REQUIRED message in the case of inter-BSC cell handover after the handover algorithm is determined.

Formula: None.

Attempted Handovers for Uplink Quality Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including internal intracell handover, internal intercell handover and outgoing inter BSC handover) caused by uplink signal quality. This item shows the frequency of handover caused by uplink signal quality in the BSC. Together with Successful Handovers for Uplink Quality, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers ,Attempted Incoming BSC Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (including internal intracell handover and internal intercell handover) or HANDOVER REQUIRED (outgoing inter BSC handover) due to uplink signal quality. This item is measured in this case.

Formula: none.

Attempted Handovers for Downlink Quality Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intracell handover, Internal intercell handover and outgoing inter BSC handover) caused by downlink signal quality. This item shows the frequency of handover caused by downlink signal quality. Together with Successful Handovers for Downlink Quality, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers ,Attempted Incoming BSC Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (Internal intracell handover and internal intercell handover) or HANDOVER REQUIRED (inter BSC handover) due to downlink signal quality. This item is measured in this case.

Formula: none.

Attempted Handovers for Uplink Strength Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to



which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intracell handover, Internal intercell handover and outgoing inter BSC handovers) caused by uplink signal strength. This item shows the frequency of handover caused by uplink signal strength. Together with Successful Handovers for Uplink Strength, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers ,Attempted Incoming BSC Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (Internal intracell handover and internal intercell handover) or HANDOVER REQUIRED (inter BSC handover) due to uplink signal strength. This item is measured in this case.

Formula: none.

Attempted Handovers for Downlink Strength Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intracell handover, Internal intercell handover and outgoing inter BSC handover) caused by downlink signal strength. This item shows the frequency of handover caused by downlink signal strength. Together with Successful Handovers for Downlink Strength, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers ,Attempted Incoming BSC Handovers and Attempted Outgoing BSC Handovers..

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (Internal intracell handover and internal intercell handover) or HANDOVER REQUIRED (inter BSC handover) due to downlink signal strength. This item is measured in this case.

Formula: none.

Attempted Handovers for Timing Advance Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intercell handover and outgoing inter BSC handover) caused by TA (because a subscriber moves far away from the serving cell but close to the target cell while talking, so the signal strength and the signal quality in serving cell drops and a handover will be triggered.). This item shows the frequency of handover caused by TA. Together with Successful Handovers for Timing Advance, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers ,Attempted Incoming BSC Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (internal intercell handover) or HANDOVER REQUIRED (inter BSC handover) due to TA. This item is measured in this case.

Formula: none.

Attempted Handovers for Better Cell Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to




which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intercell handover and outgoing inter BSC handover) caused by "better cell" (adjacent cell with lower path loss (PBGT) or higher priority). This item shows the frequency of handover caused by "better cell". Together with Successful Handovers for Better Cell, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (internal intercell handover) or HANDOVER REQUIRED (inter BSC handover) due to "better cell". This item is measured in this case.

Formula: none.

Attempted Handovers for Traffic Load Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intercell handover and outgoing inter BSC handover) caused by traffic load. This item shows the frequency of handover caused by traffic load. Together with Successful Handovers for Traffic Load, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (internal intercell handover) or HANDOVER REQUIRED (inter BSC handover) due to traffic load. This item is measured in this case.

Formula: none.

Attempted Handovers for Rapid Rxlevel Drop Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intercell handover and outgoing inter BSC handover) caused by rapid rxlevel drop. This item shows the frequency of handover caused by rapid rxlevel drop. Together with Successful Handovers for Rapid Rxlevel Drop, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (internal intercell handover) or HANDOVER REQUIRED (inter BSC handover) due to traffic load. This item is measured in this case.

Formula: none.

Attempted Handovers for Response to MSC Invocation Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intercell handover and outgoing inter BSC handover) caused by Response to MSC invocation (MSC sending HANDOVER CANDIDATE ENQUIRY to BSC which causes handovers of multiple MSs in a cell). This item shows the frequency of handover caused by Response to MSC invocation. Together with Successful Handovers for Response to MSC Invocation, this



item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (internal intercell handover) or HANDOVER REQUIRED (inter BSC handover) due to Response to MSC invocation. This item is measured in this case.

Formula: none.

Attempted Handovers for O&M Intervention Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intracell handover, Internal intercell handover and outgoing inter BSC handover) caused by O&M intervention (operation on O&M console which causes handovers, such as forced handover, no call drop blocking (blocking channels, TRXs and cells), BCCH mutual aid or TRX mutual aid). This item shows the frequency of handover caused by O&M intervention. Together with Successful Handovers for O&M Intervention, This item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers, Attempted Intercell Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (Internal intracell handover and internal intercell handovers) or HANDOVER REQUIRED (inter BSC handover) due to O&M intervention. This item is measured in this case.

Formula: none.

Attempted Handovers from Underlaid Subcell to Overlaid Subcell Description: Before originating handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of handover. The times of handover attempts of various can be measured according to this message. This item measures the times of handovers from underlaid subcell to overlaid subcell. This type of handover takes place only in IUO cells, and is regarded as a specific intracell handover. This item shows the frequency of handover from underlaid subcell to overlaid subcell. Together with Successful Handovers from Underlaid Subcell to Overlaid Subcell, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers and Attempted Handovers from Overlaid Subcell to Underlaid Subcell.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (Internal intracell handover) due to handover from underlaid subcell to overlaid subcell. This item is measured in this case.

Formula: none.

Attempted Handovers from Overlaid Subcell to Underlaid Subcell Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers from overlaid subcell to underlaid subcell. This type of handover takes place only in IUO cells, and is regarded as intracell handover. This item shows the frequency of handover from overlaid subcell to underlaid subcell. Together with Successful Handovers from Overlaid Subcell to Underlaid Subcell, this item shows the performance of handovers of this type. Related items: Attempted Intracell Handovers and Attempted Handovers from Underlaid Subcell to Overlaid Subcell.




Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (Internal intracell handover) due to handover from overlaid subcell to underlaid subcell. This item is measured in this case.

Formula: none.

Attempted Handovers for Directed Retry Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intercell handover and outgoing inter BSC handover) caused by directed retry (a handover triggered because the current cell is congested during the procedure of assignment). This item shows the frequency of handover caused by directed retry. Together withSuccessful Handovers for Directed Retry, this item shows the performance of handovers of this type. Related items: Attempted Intercell Handovers and Attempted Outgoing BSC Handovers

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (internal intercell handovers) or HANDOVER REQUIRED (inter BSC handover) due to DIRECTED RETRY. This item is measured in this case.

Formula: none.

Attempted Handovers for Other Causes Description: At the beginning of a handover, BSC will receive Handover Indication from

LAPD module. This message contains the cause value of the handover, according to which the BSC measures all kinds of handover attempts with specific handover cause. This item measures the times of handovers (including Internal intracell handover, Internal intercell handover and outgoing inter BSC handover) caused by other causes (such as fast moving, handover cause being abnormal value). This item shows the frequency of handover caused by other causes. Together with Successful Handovers for Other Causes, this item shows the performance of handovers of this type. Related items: Attempted Intercell Handovers, Attempted Intercell Handovers and Attempted Outgoing BSC Handovers.

Measurement point: After handover algorithm decision, BSC sends Intercell Handover Request (Internal intracell handover and internal intercell handovers) or HANDOVER REQUIRED (inter BSC handover) due to other causes. This item is measured in this case.

Formula: none.

Successful Handovers for Uplink Quality Description: This item measures all successful handovers caused by uplink signal quality,

including internal intracell handover, internal intercell handover and outgoing BSC handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together withAttempted Handovers for Uplink Quality this item shows the performance of handovers of this type. Related items: Intracell TCHF-TCHH Handover Attempt Times

Meaning: Intracell TCHF-TCHH handover means the handover between the half rate channel to the full rate channel in the same cell. The source cell judges whether to implement the intracell TCHF-TCHH handover based on the RQI of the current calling. The source cell and the target cell are the same one. The index “intracell TCHF-TCHH handover attempt times” is used to count the handover attempt times of the target cell. This index can also be used to know the frequency of the intracell TCHF-TCHH



handover. Together with the intracell TCHF-TCHH handover success times and the intracell TCHF-TCHH handover failure times, you can know the intracell TCHF-TCHH handover performance within the BSC.


Measurement calculation formula: none Successful Intracell Handovers, Successful Intercell Handovers and Successful Outgoing

BSC Handovers. Measurement point:

− This item is measured when the source BSC receives CLEAR COMMAND (cause: handover success) from MSC during the procedure of inter BSC handover caused by uplink signal quality.

− During the procedure of Internal intracell handover/intercell handover caused by uplink signal quality, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers for Downlink Quality Description: This item measures all successful handovers caused by downlink signal

quality, including Internal intracell handover, Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Downlink Quality, this item shows the performance of handovers of this type. Related items: Successful Intercell Handovers, Successful Intercell Handovers and Successful Outgoing BSC Handovers.


handover success) from MSC during the procedure of inter BSC handover caused by downlink signal quality.

− During the procedure of Internal intracell handover/intercell handover caused by downlink signal quality, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers for Uplink Strength Description: This item measures all successful handovers caused by uplink signal

strength, including Internal intracell handover, Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Uplink Strength, this item shows the performance of handovers of this type. Related items: Intracell TCHF-TCHH Handover Attempt Times

Meaning: Intracell TCHF-TCHH handover means the handover between the half rate channel to the full rate channel in the same cell. The source cell judges whether to implement the intracell TCHF-TCHH handover based on the RQI of the current calling. The source cell and the target cell are the same one. The index “intracell TCHF-TCHH handover attempt times” is used to count the handover attempt times of the target cell.




This index can also be used to know the frequency of the intracell TCHF-TCHH handover. Together with the intracell TCHF-TCHH handover success times and the intracell TCHF-TCHH handover failure times, you can know the intracell TCHF-TCHH handover performance within the BSC.




− This item is measured when the source BSC receives CLEAR COMMAND (cause: handover success) from MSC during the procedure of inter BSC handover caused by uplink signal strength.

− During the procedure of Internal intracell handover/intercell handover caused by uplink signal strength, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers for Downlink Strength Description: This item measures all successful handovers caused by downlink signal

strength, including Internal intracell handover, Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Downlink Strength, this item shows the performance of handovers of this type. Related items: Intracell TCHF-TCHH Handover Attempt Times





− This item is measured when the source BSC receives CLEAR COMMAND (cause: handover success) from MSC during the procedure of inter BSC handover caused by downlink signal strength.

− During the procedure of Internal intracell handover/intercell handover caused by downlink signal strength, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.



Formula: none.

Successful Handovers for Timing Advance Description: This item measures all successful handovers caused by TA (because a

subscriber moves far away from the serving cell but close to the target cell while talking, so the signal strength and the signal quality in serving cell drops and a handover will be triggered.), including Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Timing Advance, this item shows the performance of handovers of this type. Related items: Successful Intercell Handovers and Successful Outgoing BSC Handovers.


handover success) from MSC during the procedure of inter BSC handover caused by TA.

− During the procedure of BSC intercell handover caused by TA, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers for Better Cell Description: This item measures all successful handovers caused by "better cell"

(adjacent cell with lower path loss (PBGT) or higher priority), including Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Better Cell, this item shows the performance of handovers of this type. Related items: Successful Intercell Handovers and Successful Outgoing BSC Handovers.


handover success) from MSC during the procedure of inter BSC handover caused by "better cell".

− During the procedure of BSC intercell handover caused by "better cell", after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers for Traffic Load Description: This item measures all successful handovers caused by traffic load,

including Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Traffic Load, this item shows the performance of handovers of this type. Related items: Successful Intercell Handovers and Successful Outgoing BSC Handovers.

Measurement point:




− This item is measured when the source BSC receives CLEAR COMMAND (cause: handover success) from MSC during the procedure of inter BSC handover caused by traffic load.

− During the procedure of BSC intercell handover caused by traffic load, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers for Rapid Rxlevel Drop Description: This item measures all successful handovers caused by rapid rxlevel drop,

including Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Rapid Rxlevel Drop, this item shows the performance of handovers of this type. Related items: Successful Intercell Handovers and Successful Outgoing BSC Handovers.


handover success) from MSC during the procedure of inter BSC handover caused by rapid rxlevel drop.

− During the procedure of BSC intercell handover caused by rapid rxlevel drop, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers for Response to MSC Invocation Description: This item measures all successful handovers caused by Response to MSC

invocation (MSC sending HANDOVER CANDIDATE ENQUIRY to BSC which causes handovers of multiple MSs in a cell), including Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Response to MSC Invocation, this item shows the performance of handovers of this type. Related items: Successful Intercell Handovers and Successful Outgoing BSC Handovers.


handover success) from MSC during the procedure of inter BSC handover caused by Response to MSC invocation.

− During the procedure of BSC intercell handover caused by Response to MSC invocation, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers for O&M Intervention Description: This item measures all successful handovers caused by O&M intervention

(operation on O&M console which causes handovers, such as forced handover, no call drop blocking (blocking channels, TRXs and cells), BCCH mutual aid or TRX mutual aid), including Internal intracell handover, Internal intercell handover and outgoing



handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for O&M Intervention, this item shows the performance of handovers of this type. Related items: Intracell TCHF-TCHH Handover Attempt Times





− This item is measured when the source BSC receives CLEAR COMMAND (cause: handover success) from MSC during the procedure of inter BSC handover caused by O&M intervention.

− During the procedure of BSC intracell/intercell handover caused by O&M intervention, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers from Underlaid Subcell to Overlaid Subcell Description: This item measures all successful handovers from underlaid subcell to

overlaid subcell. This type of handover takes place only in IUO cells, which is a specific type of internal intracell handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. Together with Attempted Handovers from Underlaid Subcell to Overlaid Subcell, this item shows the performance of handovers of this type. Related items: Intracell TCHF-TCHH Handover Attempt Times



Measurement calculation formula: none




Successful Intracell Handovers and Successful Handovers from Overlaid Subcell to Underlaid Subcell.

Measurement point: During the procedure of handover from underlaid subcell to overlaid subcell, after MS accessed the overlaid subcell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers from Overlaid Subcell to Underlaid Subcell Description: This item measures all successful handovers from overlaid subcell to

underlaid subcell. This type of handover takes place only in IUO cells, which is a specific type of internal intracell handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. Together with Attempted Handovers from Overlaid Subcell to Underlaid Subcell, this item shows the performance of handovers of this type. Related items: Intracell TCHF-TCHH Handover Attempt Times



Measurement calculation formula: none Successful Intracell Handovers and Successful Handovers from Underlaid Subcell to

Overlaid Subcell. Measurement point: During the procedure of handover from overlaid subcell to underlaid

subcell, after MS accessed the underlaid subcell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Initiating Handovers (Frequency Offset) Description: This indicator represents the number of all successful handovers caused by

frequency offset. The handover involves both the inter-BSC cell handover and the intra-BSC cell handover. In the case of intra-BSC handover, the HANDOVER PERFORMED message sent to the MSC carries the handover cause. In the case of inter-BSC handover, the HANDOVER REQUIRED message responded to the handover carries the handover cause. Together with theAttempted Initiating Handovers (Frequency Offset) indicator, you can know the handover performance. For the related indicators, see Successful Intercell Handoversand Successful Outgoing BSC Handovers

Measurement point: − In the case of inter-BSC cell handover caused by frequency offset, the Successful

Initiating Handovers (frequency offset) is measured when the source BSC receives a CLEAR COMMAND message whose cause is handover success from the MSC.

− In the case of intra-BSC cell handover caused by frequency offset, the Successful Initiating Handovers (frequency offset) is measured when the BSC sends a



HANDOVER PERFORMED message to the MSC after the MS is successfully connected to the target cell.

Formula: None.

Successful Initiating Handovers (Quick PBGT) Description: This indicator represents the number of all successful handovers caused by

quick PBGT. The handover involves both the inter-BSC cell handover and the intra-BSC cell handover. In the case of intra-BSC cell handover, the HANDOVER PERFORMED message sent to the MSC carries the handover cause. In the case of inter-BSC cell handover, the HANDOVER REQUIRED message responded to the handover carries the handover cause. Together with theAttempted Initiating Handovers (Quick PBGT)indicator, you can know the handover performance. For the related indicators, see Successful Intercell Handovers and Successful Outgoing BSC Handovers

Measurement point: − In the case of inter-BSC cell handover caused by quick PBGT, the Successful

Initiating Handovers (quick PBGT) is measured when the source BSC receives a CLEAR COMMAND message whose cause is handover success from the MSC.

− In the case of intra-BSC cell handover caused by quick PBGT, the Successful Initiating Handovers (quick PBGT) is measured when the BSC sends a HANDOVER PERFORMED message to the MSC after the MS is successfully connected to the target cell.

Formula: None.

Successful Handovers for Directed Retry Description: This item measures all successful handovers caused by directed retry

(triggered the current cell is congested during the procedure of assignment), including Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Directed Retry, this item shows the performance of handovers of this type. Related items: Successful Intercell Handovers and Successful Outgoing BSC Handovers.


handover success) from MSC during the procedure of inter BSC handover caused by directed retry.

− During the procedure of BSC intercell handover caused by directed retry, after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Successful Handovers for Other Causes Description: This item measures all successful handovers caused by other causes (fast

moving, handover cause being abnormal value), including Internal intracell handover, Internal intercell handover and outgoing handover. For intraBSC handovers, the message HANDOVER PERFORMED to MSC contains the handover cause. For inter BSC handovers, the message HANDOVER REQUIRED corresponding to this handover contains the handover cause. Together with Attempted Handovers for Other Causes, this item shows the performance of handovers of this type. Related items: Successful




Intracell Handovers, Successful Intercell Handovers and Successful Outgoing BSC Handovers.


handover success) from MSC during the procedure of inter BSC handover caused by other causes (such as fast moving, handover cause being filled with abnormal value).

− During the procedure of BSC intercell handover caused by other causes (such as fast moving, handover cause being filled with abnormal value), after MS accessed the target cell, BSC will send HANDOVER PERFORMED to MSC. This item is measured in this case.

Formula: none.

Unsuccessful Incoming BSC Handovers (Tme Out) Description: The BSC starts HO test waiting or HO waiting timer after it receives the

incoming BSC request. If the HO test waiting or HO waiting timer times out, the BSC measures this item.

Measurement point: During incoming BSC HO, the BSC measures this item if the HO test waiting or HO waiting timer times out,

Formula: None.

Unsuccessful TCH Seizures(Error Indication) Description: When the TCH is seized, if there is an abnormal case for a radio link layer

connection, ERROR INDICATION is sent to the BSC to notify it of call drop. See GSM 0858 protocol.

Measurement point: When the BSC receives ERROR INDICATION from the TCH with the cause value “timer T200 expired(N200+1) times(0x01)”, “unsolicited DM response” and “multiple frame established state(0x05) and “sequence error (0x07)”, it measures this item.

Formula: None.

Unsuccessful TCH Seizures(Connection Failure) Description: When the TCH is seized, if there is a RL fault or hardware fault, the BSC

will send CONNECTION FAILURE INDICATION to the BSC to notify of call drop. Measurement point: When the BSC receives CONNECTION FAILURE INDICATION

from the TCH with the cause value (except “0X20-equipment failure” and “0X22-terrestrial channel failure”, it measures this item.

Formula: None.

Unsuccessful TCH Seizures(Release Indication) Description: After call setup, the BSC will start REESTABLISH (the length of time can

be adjusted) after it receives RELEASE INDICATION if the cell allows call resetup. If the call resetup timer times out, the BSC will send a request to the MSC for call clear up and measure this item.

Measurement point: This item is measured when the call resetup timer times out. Formula: None.



Unsuccessful TCH Seizures(EMLPP) Description: When the EMLPP is enabled, if the TCH for users with lower priority is

seized by that for users with higher priority, the call with lower priority will initiate a HO to other cells. If not succeed, the BSC will measure this item.

Measurement point: When a call with lower priority initiates a HO to other cells and fails, the BSC will measure this item.

Formula: None.

Unsuccessful TCH Seizures(Internal Clear) Description: During calling, if TCH serizure fails due to internal clear caused by various

reasons in the BSC, the BSC will measure this item. Measurement point: During calling, if the BSC ‘s request for an optical channel is

rejected or times out after it receives the internal clear request, it will measure this item. Formula: None.

Unsuccessful Cell Internal Handovers with Unsuccessful Reversion Description: During an intra cell HO, when HO fails and again, causing the timer

timeout, the BSC will measure this item. Measurement point: During an intra cell HO, the BSC will measure this item after

timeout. Formula: None.

Attempted Inter-System Outgoing BSC Handovers Description: The source BSC sends the MSC HANDOVER REQUIRED(containting HO

candidate cell list) to initiate a HO. The source BSC is not notified of the object cell the MSC selected or whether it is blocked, so it records the first cell is the list as the default object cell.

Measurement point: This item is measured when the source BSC sends the MSC HANDOVER REQUIRED (the object cell is the 3G neighboring cell). See Figure 3-36A1.

Formula: None.




Figure 3-36 Outgoing system HO attempts

MS RNCCNBSC UE

HANDOVER REQUIRED

A1 CR

CC

HANDOVER COMMAND

HANDOVER TO UTRAN CMD


B1


HO TO UTRAN CMPReloc Detect

Reloc CMPCLEAR COMMAND

C1

CLEAR COMPLETE

A1: Outgoing BSC HO attempts B1: Outgoing BSC HOs C1: Out system HO successes

Inter-System Outgoing BSC Handovers Description: During the inter-system handover, the original BSC sends the message

"HANDOVER TO UTRAN COMMAND" to MS. MS accesses to the target cell successfully. After receive the message "CLEAR COMMAND" (cause value: handover success) from MSC the original BSC clears the old resource. The handover is complete.

Measurement point: This item is measured when the original BSC receives the message "CLEAR COMMAND" (cause value: handover success) from MSC (CN) during the inter-system handover. See Figure 3-36 C1.

Formula: None.

Successful Inter-System Outgoing BSC Handovers Description: During the inter-system handover, after the target BSC(RNC) prepares the

new channel, it generates the message "HANDOVER TO UTRAN COMMAND" and then sends the message to the original BSC through MSC(CN). After the original BSC receives the message "HANDOVER TO UTRAN COMMAND", it forwards the message to the MS.

Measurement point: This item is measured when the original BSC receives the message "HANDOVER COMMAND" (the target cell is 3G neighboring cell) during the inter-system handover. See Figure 3-36 B1 .

Formula: None.

Unsuccessful Inter-System Outgoing BSC Handovers with Successful Reversion Description: During the inter-system handover, the original BSC sends the message

"HANDOVER COMMAND" to the MS. If the MS fails to access to the target cell due to the radio environment, equipment failure or handover parameter error, the MS sends the message "HANDOVER FAILURE" (cause value: Radio interface failure, and reversion



to old channel) to the original BSC on the old channel. After receive the message, the BSC forwards it to the MSC. Then, the MSC notifies the target BSC (RNC) to clear the resources related to this handover. The MS restores the connection on the original BSC.

Measurement point: During an inter system HO, this item is measured when the source BSC receives from the MS HANDOVER FAILURE(with the causes “Radio interface failure” and “reversion to old channel”) . See Figure 3-37 A1.

Formula: None.

Figure 3-37 Unsuccessful outgoing system HOs

BTS CNBSC

HANDOVER REQUIRED

HANDOVER COMMAND


HANDOVER FAILUREHANDOVER FAILURE

CONN FAIL IND

A1

B1ERROR INDICATION

B3

B2CLEAR COMMAND

CLEAR COMMAND

CLEAR CMP

A1: Unsuccessful inter system outgoing BSC HOs with successful reversion B1−B3: Unsuccessful inter system outgoing BSC HOs with unsuccessful reversion

Unsuccessful Inter-System Outgoing BSC Handovers with Unsuccessful Reversion

Description: During the inter-system handover, the original BSC sends the message "HANDOVER COMMAND" to MS. If the MS fails to access to the target cell and disconnects with the original BSC due to the bad radio link quality, handover parameter error or equipment failure, the BSC sends the message "CLEAR REQUEST" to MSC to clear the old resource and the handover resource.

Measurement point: This item is measured when the original BSC receives the message "CONNECTION

FAILURE INDICATION" (bad radio link quality) from BTS during the inter-system handover. See Figure 3-37 B1.

This item is measured when the original BSC receives the message "ERROR INDICATION (cause value: "timer T200 expired (N200+1) times”, ” unsolicited DM response, multiple frame established state” or ”sequence error”). See Figure 3-37 B2.

During an inter system HO, this item is measured when the source BSC receives from the MSC CLEAR COMMAND (with the cause value “none handover success”). See Figure 3-37 B3.




During an itner system HO, this item is measured when the source BSC wait for CLEAR COMMAND(with the cause value “none handover success”) from the MSC times out.

Formula: None.

Inter-System Outgoing BSC handover success rate Description: See “Successful Inter-System Outgoing BSC Handovers”, “Attempted

Inter-System Outgoing BSC Handovers”. Measurement point: none. Formula: Successful Inter-System Outgoing BSC Handovers/Attempted Inter-System

Outgoing BSC Handovers

Inter-System radio Outgoing BSC handover success rate Description: See “Successful Inter-System Outgoing BSC Handovers”, “Inter-System

Outgoing BSC Handovers”. Measurement point: none. Formula: Successful Inter-System Outgoing BSC Handovers/ Inter-System Outgoing

BSC Handovers

3.2 SCCP Measurement Function 3.2.1 General

In SS7 protocol system, SCCP (Signaling Connection Control Part) and MTP (Message Transfer Part) provide a comprehensive network function for the data of application part. SCCP provides two types of services: connectionless service and connection-oriented service.

Connectionless service transmits signaling in the signaling network directly using the routing function of SCCP and MTP without establishing signaling connection before transmitting the signaling data. It is flexible and simple, and applicable for transmission of small amount data.

Connection-oriented service needs to establish a signaling connection (virtual connection) between calling SCCP and called SCCP in request-response mode before transmitting signaling data. This connection is used to transmit signaling. When transmission is completed, the relative message will be sent to request for releasing the signaling connection. This type of service is applicable for transmission of large amount data.

SCCP Measurement Function shows the flow of important messages under two types of SCCP services at A interface. It can be used to analyze the operation of SCCP system, and locate the faults at A interface signaling link layer.

All the statistic items are listed in Table 3-5.

Table 3-5 Statistic items in SCCP Measurement Function

No. Item name

1 UDT Messages (O)

2 UDT Messages (I)



No. Item name

3 XUDT Messages (O)

4 XUDT Messages (I)

5 CR Messages (O)

6 CR Messages (I)

7 CC Messages (O)

8 CC Messages (I)

9 CREF Messages (O)

10 CREF Messages (I)

11 DT1 Messages (O)

12 DT1 Messages (I)

13 RLSD Messages (O)

14 RLSD Messages (I)

15 RLC Messages (O)

16 RLC Messages (I)

17 Opposite SCCP Reject Rate(%)

18 Local SCCP Reject Rate(%)

3.2.2 Statistic Items

UDT Messages (O) Description: The connectionless service provided by SCCP uses the messages

UNITDATA (UDT) and EXTENDED UNITDATA (XUDT) to transmit user data. UNITDATA does not have the capability of data segmenting/reassembling. The maximum length of user data it can transmit is 128 octets. EXTENDED UNITDATA is capable of segmenting/reassembling data. The maximum length of user data it can transmit is 2048 octets.

Measurement point: When SCCP service module of BSC sends UNITDATA, the number of UDT messages (O) is increased by 1.

Formula: none.

UDT Messages (I) Description: The connectionless service provided by SCCP uses the messages





Measurement point: When SCCP service module of BSC receives UNITDATA from the peer SCCP service module, the number of UDT messages (I) is increased by 1.

Formula: none.

XUDT Messages (O) Description: The connectionless service provided by SCCP uses the messages


Measurement point: When SCCP service module of BSC sends EXTENDED UNITDATA, the number of XUDT messages (O) is increased by 1.

Formula: none.

XUDT Messages (I) Description: The connectionless service provided by SCCP uses the messages


Measurement point: When SCCP service module of BSC receives EXTENDED UNITDATA from the peer SCCP service module, the number of XUDT messages (I) is increased by 1.

Formula: none.

CR Messages (O) Description: Connection-oriented service needs to establish a signaling connection

(virtual connection) between calling SCCP and called SCCP in request-response mode before transmitting signaling data. Figure 3-38 illustrates the process of creating a successful signaling connection. The calling SCCP sends Connection Request (CR) to the called SCCP to request the setup of a signaling connection between the two entities. On reception of a Connection Request, the called SCCP initiates the setup of the signaling connection, and then sends Connection Confirm (CC) to the calling SCCP. On reception of Connection Confirm, the calling SCCP completes the setup of the signaling connection.

Measurement point: When SCCP service module of BSC sends Connection Request, the number of CR messages (O) is increased by 1.

Formula: none.



Figure 3-38 Establishment of SCCP signaling connection (successful)

SCCP-A SCCP-B

CONNECTION REQUEST

A B

C D

CONNECTION CONFIRM

A: CR messages (O) B: CR messages (I) C: CC messages (I) D: CC messages (O)

CR Messages (I) Description: Connection-oriented service needs to establish a signaling connection

(virtual connection) between calling SCCP and called SCCP in request-response mode before transmitting signaling. Figure 3-38 illustrates the process of creating a successful signaling connection. The calling SCCP sends Connection Request (CR) to the called SCCP to request the setup of a signaling connection between the two entities. On reception of a Connection Request message, the called SCCP initiates the setup of the signaling connection, and then sends Connection Confirm (CC) to the calling SCCP. On reception of Connection Confirm, the calling SCCP completes the setup of the signaling connection.

Measurement point: When SCCP service module of BSC receives Connection Request from the peer SCCP service module, the number of CR messages (I) is increased by 1.

Formula: none.

CC Messages (O) Description: Connection-oriented service needs to establish a signaling connection

(virtual connection) between calling SCCP and called SCCP in request-response mode before transmitting signaling. Figure 3-38 illustrates the process of creating a successful signaling connection. The calling SCCP sends Connection Request (CR) to the called SCCP to request the setup of a signaling connection between the two entities. On reception of a Connection Request, the called SCCP initiates the setup of the signaling connection, and then sends Connection Confirm (CC) to the calling SCCP. On reception of Connection Confirm, the calling SCCP completes the setup of the signaling connection.

Measurement point: When SCCP service module of BSC sends Connection Confirm, the number of CC messages (O) is increased by 1.

Formula: none.

CC Messages (I) Description: Connection-oriented service needs to establish a signaling connection

(virtual connection) between calling SCCP and called SCCP in request-response mode before transmitting signaling. Figure 3-38 illustrates the process of creating a successful




signaling connection. The calling SCCP sends Connection Request (CR) to the called SCCP to request the setup of a signaling connection between the two entities. On reception of a Connection Request, the called SCCP initiates the setup of the signaling connection, and then sends Connection Confirm (CC) to the calling SCCP. On reception of Connection Confirm, the calling SCCP completes the setup of the signaling connection.

Measurement point: When SCCP service module of BSC receives Connection Confirm from the peer SCCP service module, the number of CC messages (I) is increased by 1.

Formula: none.

CREF Messages (O) Description: Connection-oriented service needs to establish a signaling connection

(virtual connection) between calling SCCP and called SCCP in request-response mode before transmitting signaling. After calling SCCP initiates Connection Request, the called SCCP or an intermediate node SCCP may refuse the connection for some reason. In this case, they will initiate CONNECTION REFUSED (cref). See Figure 3-39.

Measurement point: When SCCP service module of BSC sends CONNECTION REFUSED, the number of CREF messages (O) is increased by 1.

Formula: none.

Figure 3-39 Establishment of SCCP signaling connection (failure)

SCCP-A

CONNECTION REQUEST

A

CONNECTION REFUSED

SCCP-B

B

A: CREF messages (I) B: CREF messages (O)

CREF Messages (I) Description: Connection-oriented service needs to establish a signaling connection

(virtual connection) between calling SCCP and called SCCP in request-response mode before transmitting signaling. After calling SCCP initiates Connection Request, the called SCCP or an intermediate node SCCP may refuse the connection for some reason. In this case, they will initiate CONNECTION REFUSED (cref). See Figure 3-39.

Measurement point: When SCCP service module of BSC receives CONNECTION REFUSED from the peer SCCP service module, the number of CREF messages (I) is increased by 1.

Formula: none.



DT1 Messages (O) Description: Connection-oriented service needs to establish a signaling connection

(virtual connection) between calling SCCP and called SCCP in request-response mode before transmitting signaling data. DATA FORM 1 (DT1) is used in transmitting signaling between SCCP signaling points. When a SCCP needs to transmit signaling, it will send DT1 containing the signaling to the peer SCCP. On reception of this DT1, the peer SCCP will also respond with a DT1 containing signaling. See Figure 3-40.

Measurement point: When SCCP service module of BSC sends DATA FORM 1, the number of DT1 messages (O) is increased by 1.

Formula: none.

Figure 3-40 Establishment of SCCP signaling connection and data transmission

SCCP-A

CONNECTION REQUEST

A

CONNECTION CONFIRM

SCCP-B

B

DATA FORM 1

DATA FORM 1

A: DT1 messages (I) B: DT1 messages (O)

DT1 Messages (I) Description: Connection-oriented service needs to establish a signaling connection

(virtual connection) between calling SCCP and called SCCP in request-response mode before transmitting signaling data. DATA FORM 1 (DT1) is used in transmitting signaling between SCCP signaling points. When a SCCP needs to transmit signaling, it will send DT1 containing the signaling to the peer SCCP. On reception of this DT1, the peer SCCP will also respond with a DT1 containing signaling. See Figure 3-40.

Measurement point: When SCCP service module of BSC receives DATA FORM 1 from the peer SCCP service module, the number of DT1 messages (I) is increased by 1.

Formula: none.

RLSD Messages (O) Destination: RELEASED (RLSD) is sent, in the forward or backward direction, to

indicate that the sending SCCP wants to release a signaling connection and the associated resources. On reception of this message, the receiving SCCP should release the connection and any other associated resources as well. A RELEASE COMPLETE (RLC) message is sent in response to the RELEASED message indicating that the RELEASED message has been received, and the appropriate procedures have been completed. See Figure 3-41.




Measurement point: When SCCP service module of BSC sends RELEASED, the number of RLSD messages (O) is increased by 1.

Formula: none.

Figure 3-41 Transmission of SCCP signaling

SCCP-A

CONNECTION REQUEST

C

CONNECTION CONFIRM

SCCP-B

D

DATA FORM 1

DATA FORM 1

RELEASED

RELEASE COMPLETE

A B

A: RLSD messages (O) B: RLSD messages (I) C: RLC messages (I) D: RLC messages (O)

RLSD Messages (I) Destination: RELEASED (RLSD) is sent, in the forward or backward direction, to


Measurement point: When SCCP service module of BSC receives RELEASED from the peer SCCP service module, the number of RLSD messages (I) is increased by 1.

Formula: none.

RLC Messages (O) Destination: RELEASED (RLSD) is sent, in the forward or backward direction, to


Measurement point: When SCCP service module of BSC sends RELEASE COMPLETE, the number of RLC messages (O) is increased by 1.



Formula: none.

RLC Messages (I) Destination: RELEASED (RLSD) is sent, in the forward or backward direction, to


Measurement point: When SCCP service module of BSC receives RELEASE COMPLETE from the peer SCCP service module, the number of RLC messages (I) is increased by 1.

Formula: none.

Opposite SCCP Reject Rate(%) Description: See CREF Messages (I),CREF Messages (O). Measurement point: None. Formula: CREF Messages (I) / CREF Messages (O)

Local SCCP Reject Rate(%) Description: See CREF Messages (O), CREF Messages (I). Measurement point: None. Formula:CREF Messages (O) / CREF Messages (I)

3.3 A-Interface Operation and Management Statistic 3.3.1 General

"A-interface Operation and Management Statistic" reflect the O&M and running status of BSC equipment, as well as concern the interworking between BSC and MSC, including reset of MSC, reset of BSC, reset, fault and recovery of a single module in BSC, the overall running status of A interface signaling, BSC's handling procedure after MSC overload, etc. See Table 3-6 for the list of all the relevant statistic items.

Table 3-6 Statistic items in A-interface Operation and Management Statistic

No. Item name

1 BSC Initiated Reset

2 MSC Initiated Reset

3 Single Module (BSC) Initiated Reset

4 Internal Notifications of BSC Reset

5 Internal Notifications of MSC Reset

6 Internal Notifications of BM Reset




No. Item name

7 BSC BM Suspend

8 BSC BM Resume

9 BSC Overload

10 SS7 Link Connections

11 SS7 Link Breakdowns


BSC Initiated Reset Description: After the user initiates reset of BSC in BSC Maintenance System, BSC

Maintenance System sends an MT_RESET_RESOURCE message to BSC. Upon receipt of the message, BSC shall execute the command. When BSC is reset, all the calls within it shall be cleared (In the subsequent 128 seconds, the establishment of new calls shall be prohibited). In the meantime, BSC shall send a RESET message to MSC and await the response message (RESET_ACK). The timer value for awaiting the RESET_ACK message is 150 second. BSC shall resend the RESET message, if it cannot receive the RESET_ACK message before the timer expires. Such repeat operations can be performed for max. 3 times. This statistic item is used calculate the number of RESET message sent from BSC to MSC.

Measurement point: Statistics will be made when BSC sends a RESET message to MSC. Formula: none

MSC Initiated Reset Description: MSC sends a RESET message to BSC when it is reset. Upon receipt of the

RESET message, BSC returns a RESET_ACK message, and at the same time, it clears all the CS calls (GPRS calls no impact) within BSC and prohibits the establishment of new calls in the subsequent 128s. This item is used calculate the number of times BSC receives RESET messages from MSC.

Measurement point: Statistics will be made when BSC receives a RESET message from MSC.

Formula: none

Single Module (BSC) Initiated Reset Description: When a single BM is reset, the calls in all the cells under this module shall

be cleared (The establishment of new calls shall be prohibited in the subsequent 128s). At the same time, this BM shall notify other BMs to clear the calls that occupy its A interface circuit resources. This item is used calculate the number of times a single BM is reset. In the following cases, a single module shall be reset. − The user resets a BM in BSC Maintenance System. − The communication between BM and AM/CM is resumed after interruption. − When the communication between BM and AM/CM is resumed after interruption, the

communication on A interface of BSC is in interruption state (The SS7 links of the



whole BSC are disconnected), but afterwards, BM detects that the communication on A interface is resumed.

− The first time BM detects that the communication on A interface is normal after kickoff (At least 1 SS7 link is normal).

Measurement point: Statistics will be made when a single BM is reset and calls are cleared.

Formula: none

Internal Notifications of BSC Reset Description: This item is correlated with "BSC initiated reset". After user initiates reset

of BSC in BSC Maintenance System, the BM with the smallest module No. among the BMs of BSC that work normally shall serve as the main control BM, sends an INTER_BSC_RESET_IND message to the other BMs notifying them to clear calls, and await the response messages. The timer value for awaiting the response messages is 2 second. The BM shall resend the message if it has not received the response messages before expiry of the timer. This statistic item is to calculate the times of the main control BM notifying the other BMs to clear calls during BSC reset.

Measurement point: Statistics will be made when the other BMs receive an INTER_BSC_RESET_IND message from the main control BM during BSC reset.

Formula: none.

Internal Notifications of MSC Reset Description: This item is correlated with "MSC initiated reset". MSC sends a RESET

message to BSC when MSC is reset. After BSC receives the message, the BM with the smallest module No. among the BMs of BSC that work normally shall serve as the main control BM, return an RESET_ACK message to MSC, clear all the CS calls (GPRS services are free from the impact) of itself, send an INTER_MSC_RESET_IND message to the other BMs notifying them to clear CS calls, and await the response messages. The timer value for awaiting the response message is 2 second. The BM shall resend the message if it has not received the response messages before expiry of the timer. This statistic item is to calculate the times of the main control BM in BSC notifying other BMs to clear CS calls after BSC receives a RESET message from MSC.

Measurement point: After BSC receives a RESET message from MSC, the main control BM sends an INTER_MSC_RESET_IND message to other BMs. When the other BMs receive INTER_MSC_RESET_IND and clear CS calls, statistics will be made.

Formula: none.

Internal Notifications of BM Reset Description: This item is correlated with "Single module (BSC) initiated reset". When a

single BM is reset, the BM shall send an INTER_BSC_BM_RESET_IND message to other BMs notifying them to clear the calls that occupy its A interface circuit resources, and await the response messages. The timer value for awaiting the response message is 2 second. The BM shall resend the message if it has not received the response message before expiry of the timer. This statistic item is to calculate the times of a BM notifying other BMs to clear the calls that occupy its A interface circuit resources when it is reset.

Measurement point: Upon reset, a BM sends an INTER_BSC_BM_RESET_IND message to other BMs. When the other BMs receive INTER_BSC_BM_RESET_IND and clear the calls that occupy the A interface circuit resources of that BM, statistics will be made.

Formula: none.




BSC BM Suspend Description: "BM suspend" means that after the communication between AM/CM and a

BM in BSC is interrupted, the BM shall clear all the calls as well as prohibit establishment of new calls in it, and disconnect its SS7 link. This statistic item is used to calculate the number of times the communication between BM and AM/CM is interrupted. The BM whose communication is interrupted is to make statistics.

Measurement point: Statistics will be made when BM detects that the communication between AM/CM and itself is interrupted.

Formula: none.

BSC BM Resume Description: This statistic item is correlated with "BSC BM suspend". "BM resume"

means that the communication between BM and AM/CM is resumed after interruption. This item is to calculate the times of that the communication between BM and Am/CM is resumed after interruption. The BM whose communication is interrupted is to make the statistics. BM will be automatically reset after its communication with AM/CM is resumed. For relevant description, please refer to "Single module (BSC) initiated reset".

Measurement point: Statistics will be made when BM detects that its communication with AM/CM is resumed after interruption.

Formula: none.

BSC Overload Description: After overload occurs to MSC, MSC sends an OVERLOAD message to

BSC. Upon receipt of the OVERLOAD message, BSC starts the corresponding flow control algorithm or raise the flow control level. According to the algorithm, BSC shall discard a proportion of calls that are being established so as to lessen the severity of MSC overload. According to the algorithm, if BSC no longer receives any OVERLOAD messages from MSC within a period of time, the flow control level will be automatically lowered, and the proportion of discarded calls will be reduced until no flow control is required. This item is to calculate the times of overload occur to MSC.

Measurement point: Statistics will be made when BSC receives an OVERLOAD message from MSC.

Formula: none.

SS7 Link Connections Description: "SS7 link connection" refers to the normal connection of SCCP layer

between MSC and BSC on A interface. When the SCCP layer satisfies the following conditions at the same time, the connection will be regarded as "normal". Otherwise, it will be regarded as "breakdown". − Permitted by DPC − No congestion − SCCP available

This statistic item is to calculate the times of SCCP connection are resumed. Measurement point:

− The first time BM detects that the SCCP connection on A interface is normal after kickoff.

− When BM detects that the state of SCCP connection on A interface has changed from "breakdown" into "normal".



Formula: none.

SS7 Link Breakdowns Description: This statistic item is correlated with "SS7 link connections". When the

SCCP layer of BSC on A interface satisfies the following conditions at the same time, the connection will be regarded as "normal". Otherwise, it will be regarded as "breakdown". − Permitted by DPC − No congestion − SCCP available

This statistic item is to calculate the times of SCCP connection state changes from "normal" into "breakdown".

Measurement point: Statistics will be made when BM detects that the SCCP connection on A interface is broken down.

Formula: none.

3.4 A-interface Equipment Maintenance Statistic 3.4.1 General

"A-interface Equipment Maintenance Statistic" reflects the operations performed by users to A interface trunk circuits and board equipment, including user-initiated block, unblock, setting, reset, etc. See Table 3-7 for the list of all the relevant statistic items.

Table 3-7 Statistic items in A-interface Equipment Maintenance Statistic

No. Item name

1 Act of Setting Trunk Circuit Table Dynamically

2 Act of Unblocking Circuits

3 Act of Blocking Circuits

4 Act of Resetting Circuits

5 Act of Resetting FTC Boards

6 Act of Resetting SM Boards


Act of Setting Trunk Circuit Table Dynamically Description: The user implements dynamic data configuration to send the trunk circuit

table to one or more BMs. According to the data received, BM refreshes the A interface circuit management table in memory. This statistic item is to calculate the number of A interface trunk circuits in this BM after the A interface circuit management table is updated(including the A interface trunk circuits that are not installed)




Measurement point: Statistics will be made when BM receives a trunk circuit table from Data Management System.

Formula: none.

Act of Unblocking Circuits Description: When the user performs an unblocking operation for A interface circuits via

BSC Maintenance System, BSC Maintenance System sends an MT_OPEN_CIRCUIT message to the corresponding BM of BSC, which contains the range of the to-be-unblocked circuits. Upon receipt of the message, BM modifies the states of the circuits in the specified range, notifies MSC about the state modifications through the GROUP_UNBLOCK_CIRCUIT and UNBLOCK_CIRCUIT messages, and awaits the response message. BM will resend the messages to MSC if it cannot receive a response message within 150 second. The max. number of resending is 2. This statistic item is to calculate the times of the user performs unblocking operations in BSC Maintenance System.

Measurement point: When BM modifies the states of circuits upon receipt of the MT_OPEN_CIRCUIT message from BSC Maintenance System, statistics will be made.

Formula: none.

Act of Blocking Circuits Description: When the user performs a blocking operation for A interface circuits via

BSC Maintenance System, BSC Maintenance System sends an MT_BLOCK_CIRCUIT message to the corresponding BM of BSC, which contains the range of the to-be-blocked circuits. Upon receipt of the message, BM modifies the states of the circuits in the specified range, notifies MSC about the state modifications through the GROUP_BLOCK_CIRCUIT and BLOCK_CIRCUIT messages, and awaits the response message. BM will resend the messages to MSC if it cannot receive a response message within 150 second. The max. number of resending is 2. If a circuit within the range is being occupied by a call, the circuit state will be changed into "blocked" after the call is terminated. This statistic item is to calculate the times of the user performs blocking operations in BSC Maintenance System.

Measurement point: When BM modifies the states of circuits upon receipt of the MT_BLOCK_CIRCUIT message from BSC Maintenance System, statistics will be made.

Formula: none.

Act of Resetting Circuits Description: When the user performs a reset operation for A interface circuits via BSC

Maintenance System, BSC Maintenance System sends an MT_RESET_CIRCUIT message to the corresponding BM of BSC, which contains the range of the to-be-reset circuits. Upon receipt of the message, BM changes the states of the blocked circuits in the specified range into "idle", sends RESET_CIRCUIT messages one by one to MSC, and awaits the response messages. BM will resend the message to MSC if it cannot receive a response message within 150 second. The max. number of resending is 2. Upon receipt of the RESET_CIRCUIT message, MSC first judges whether the circuit is being occupied by a call, clears the call if it occupies the circuit, and then returns RESET_CIRCUIT_ACK message to BSC. This statistic item is to calculate the number of times the user performs reset operations in BSC Maintenance System.

Measurement point: When BM receives an MT_RESET_CIRCUIT message from BSC Maintenance System, statistics will be made.



Formula: none.

Act of Resetting FTC Boards Description: When the user resets FTC via BSC Maintenance System, BSC Maintenance

System sends a RESET_FTC message to the corresponding BM of BSC. Upon receipt of the message, the BM implements reset operation for FTC. This statistic item is to calculate the times of the user performs FTC reset operations in BSC Maintenance System.

Measurement point: When BM resets FTC after it receives a RESET_FTC message from BSC Maintenance System, statistics will be made.

Formula: none.

Act of Resetting SM Boards Description: When the user resets an SM board via BSC Maintenance System, BSC

Maintenance System sends a RESET_SM message to the corresponding BM in BSC. Upon receipt of the message, the BM implements reset operation for the SM board. This statistic item is to calculate the times of the user performs SM reset operations in BSC Maintenance System.

Measurement point: When BM resets SM board after it receives a RESET_SM message from BSC Maintenance System, statistics will be made.

Formula: none.

3.5 A-interface Trunk Board Message Statistic 3.5.1 General

"A-interface Trunk Board Message Statistic" reflects the operational state of A interface hardware equipment, including board reset, E1 trunk reset, fault and recovery. See Table 3-8 for the list of all the relevant statistic items.

Table 3-8 Statistic items in A-interface Operation and Management Statistic

No. Item name

1 FTC Board Reset Messages

2 FTC Board Errors

3 SM Board Reset Messages

4 SM Board Errors

5 E3M Board Errors

6 E1 Errors

7 E1 Recovery

8 E1 Warnings





FTC Board Reset Messages Description: After FTC is successfully reset, a report is sent to BM, notifying it about the

success of FTC reset. Upon receipt of the message, BM sets the state of the FTC as "normal", and sends configuration information to the FTC. This statistic item is to calculate the times of FTC reports success of FTC reset to BM.

Measurement point: When BM receives a message from FTC, indicating that the FTC is successfully reset, statistics will be made.

Formula: none.

FTC Board Errors Description: When an FTC fault is detected, BM will set the state of the FTC as "faulty".

This statistic item is to calculate the times of BM detects FTC faults. if the FTC is “not visible”, this statistic item is not to be calculated.

Measurement point: When BM detects that FTC becomes faulty, statistics will be made. Formula: none.

SM Board Reset Messages Description: After an SM board is successfully reset, a report is sent to BM, notifying it

about the success of SM reset. Upon receipt of the message, BM sets the state of the SM board as "normal". This statistic item is to calculate the times of the SM board reports success of SM reset to BM.

Measurement point: When BM receives a message from a SM board, indicating that the SM board is successfully reset, statistics will be made.

Formula: none.

SM Board Errors Description: When an SM board fault is detected, BM will set the state of the SM board

as "faulty". This statistic item is to calculate the times of BM detects SM board faults. Measurement point: When BM detects that an SM board becomes faulty, statistics will

be made. Formula: none.

E3M Board Errors Description: When an E3M board fault is detected, BM will set the state of the E3M

board as "faulty". This statistic item is to calculate the number of times BM detects E3M board faults.

Measurement point: When BM detects that an E3M board becomes faulty, statistics will be made.

Formula: none.

E1 Errors Description: When an E1 trunk on A interface becomes faulty, FTC/SM reports the E1

trunk fault to BM. BM will also consider that a fault has occurred to the relevant A interface E1 trunk when it detects FTC/SM/E3M becomes faulty. BM will refresh E1



state and relevant A interface circuit state. This statistic item is to calculate the times of faults occur to the A interface trunk.

Measurement point: − When BM receives a report from SM, notifying that a fault has occurred to an E1

trunk. − When BM detects an FTC/SM/E3M fault.

Formula: none.

E1 Recovery Description: FTC/SM reports E1 trunk recovery to BM when it detects that an E1 trunk

on A interface has recovered from fault. BM will refresh the E1 state and relevant A interface circuit state. This statistic item is to calculate the times of A interface trunk recovers from fault.

Measurement point: When BM receives an E1 trunk recovery report, statistics will be made.

Formula: none.

E1 Warnings Description: When the state of an A interface E1 trunk changes (from "normal" to

"faulty", or from "faulty" to "normal"), BM will report an alarm to the alarm system (Alarm No.: 317. Alarm name: A interface E1 state reporting). This statistic item is to calculate the times of alarm 317 is reported.

Measurement point: When BM reports alarm 317 to the alarm system, statistics will be made.

Formula: none.

3.6 CPU Measurement Function 3.6.1 General

CPU measurement function includes two statistic items: Percentage of CPU occupation (%) and Peak percentage of CPU occupation (%), see Table 3-9.

The former one is the percentage of CPU in busy status during the measurement cycle. This item indicates the load of BSC. The latter one is the maximum CPU occupation within measurement cycle.

CPU occupation rate indicates the load of system. But 100% CPU occupation does not mean that the processing capacity of CPU has been fully exerted, and no more tasks can be accepted. Since BSC has some buffering capability, newly arrived tasks can be stored in the buffer. Theoretically, as long as enough internal buffering space of BSC still exists, BSC is able to accept new service requests, and the service will not be interrupted. In other words, high CPU occupation does not always indicate BSC failure. In practice, sometime, CPU occupation may go higher than 80%.

However, the internal buffering space of BSC is limited. If CPU occupation hooks on high values for a long time, the BSC internal buffering space may be exhausted at a certain instant because the arrival model of service requests is unexpectable. In this case, the new service requests might be discarded.




Try to avoid the following operations in the case of high CPU occupation:

Setting large amount of data on-line; Resetting BTS or board, or loading software to board; Implementing interface signaling tracing.

It is recommended to register this task on any occasion.

In practice, if CPU occupation is higher than 80%, the network is likely in abnormal status. The following can be the causes of high CPU occupation: long period of large scope link disconnection between BTS and BSC (the duration of link disconnection is longer than the period of MS periodical location update), large number of MSs simultaneously implementing location update after recovery of transmission link, short message broadcasting to entire network at NSS.

Measurement object: BM.

Recommended period: 30 minutes.

Table 3-9 Statistic items in CPU Measurement Function

No. Item name

1 Percentage of CPU Occupation (%)

2 Peak Percentage of CPU Occupation (%)


Percentage of CPU Occupation (%) Description: This item measures the percentage of CPU in busy status during the

measurement cycle. "CPU in busy status" can be that CPU is process system message or timing task. It is opponent to "CPU in idle status", which means that the ready message queue of operation system is empty, no clock interruption occurs and CPU is waiting for clock interruption.

The internal sampling period of CPU occupation in BSC is 10 seconds. The occupation is obtained by calculating idle rate. This means whenever CPU is idle, the duration of its idle time is summed up. After 10 seconds, the percentage of idle time is calculated, and then the CPU occupation is obtained by subtracting this percentage from 1.

Measurement point: Whenever CPU is idle, the duration of its idle time is summed up every 10 seconds.

Formula: none.

Peak Percentage of CPU Occupation (%) Description: Maximum CPU occupation within the measurement cycle. Measurement point: Whenever a higher CPU occupation is found within the period, its

value is recorded. Formula: none.



3.7 BSC Cell Broadcast Measurement 3.7.1 General

BSC Cell Broadcast Measurement provides statistic items for the measurement of operations of Cell Broadcast short message service (CBS) in the entire BSC. It contains three measurement types: BSC Cell Broadcast Measurement Function (Total), BSC Cell Broadcast Measurement Function (Period), BSC Cell Broadcast Measurement Function (Others). Because of the correlation of items in the first two measurement types, it is required that all the items of one measurement type be registered in the same task.

Note: The items of BSC Cell Broadcast Measurement Function (Total) are the accumulated values during the operation of BSC cell broadcast module. The items of BSC Cell Broadcast Measurement Function (Period) and BSC Cell Broadcast Measurement Function (Others) are the accumulated values during the statistic period.

To know the operation of the cell broadcast of a specified cell, it is necessary to register the relative items in Cell Broadcast Statistic.

The object of BSC cell broadcast measurement is the entire BSC. The Object Info window of task registration should display "The task needn’t special parameter". The recommended statistic cycle is 60 minutes.

Below are the details of each item, including the description, measurement point and formula. "Description" briefly introduces the trigger process and trigger cause, and the focus here is message interaction between Cell Broadcast Center (CBC) and BSC. "Measurement point" lists the causes that trigger the measurement of this item. None of the items here has measurement formula.

3.7.2 BSC Cell Broadcast Measurement Function (Total) Table 3-10 lists all statistic items of BSC Cell Broadcast Measurement Function (Total).

Table 3-10 Statistic items in BSC Cell Broadcast Measurement Function (Total)

No. Item name

1 Received "Write-Replace" Messages

2 Received "Kill Request" Messages

3 Received "Status-CBCH-Query" Messages

4 Received "Status-Message-Query" Messages

5 Received "Set-DRX" Messages

6 Received "Reset Request" Messages

7 Reports to "Write-Replace" Message

8 Rejections to "Write-Replace" Message

9 Reports to "Kill Request" Message

10 Rejections to "Kill Request" Message

11 Reports to "Status-CBCH-Query" Message




No. Item name

12 Rejections to "Status-CBCH-Query" Message

13 Reports to "Status-Message-Query" Message

14 Rejections to "Status-Message-Query" Message

15 Reports to "Set-DRX" Message

16 Rejections to "Set-DRX" Message

17 Sent "Restart-Indication" Messages

18 Rejections to "Reset Request" Messages

19 Sent "Failure-Indication" Messages

20 CBCH Overload (Overflow)

21 CBCH Overload (Underflow)

22 Received "Write" Messages

23 Reports to "Write" Messages

24 Rejections to "Write" Messages

25 Received "Replace" Messages

26 Reports to "replace" Messages

27 Rejections to "Replace" Messages

28 Capacity of Message Library

29 Disconnected Times of BM 1








37 Disconnected Times of CBC

Received "Write-Replace" Messages Description: CBC sends a WRITE-REPLACE message to the BSC when a new message

is created or a message already broadcast is modified. After receiving this message and confirming its correctness, BSC will judge whether it is a new message or a substitute. If it is a new message, it will store it in the message library. If it is a substitute message, it will delete the corresponding old message, and then store the new one in the message



library. Next, BSC sends REPORT Response to CBC. If the WRITE-REPLACE message BSC receives is incorrect (not conforming to ETSI GSM 03.41), BSC will return REJECT Response. Related items: Reports to "Write-Replace" Message and Rejections to "Write-Replace" Message.

Measurement point: As shown in Figure 3-42 A, this item is measured when BSC receives WRITE-REPLACE from CBC regardless of the correctness of this message.

Formula: None.

Figure 3-42 Send broadcast short message

CBC BSC

WRITE-REPLACE Request

REPORT Response

A

REJECT Response C

B

A: Received "write-replace" messages B: Reports to "write-replace" message C: Rejections to "write-replace" message

Received "Kill Request" Messages Description: CBC sends a KILL Request message to the BSC when a Cell Broadcast

(CB) message sent to the specified (one or multiple) cells is deleted. After receiving this message and confirming its correctness, BSC will delete it from the message library. Next, BSC sends REPORT Response to CBC. If the KILL Request BSC receives is incorrect, BSC will return REJECT Response. Related items: Reports to "Kill Request" Message and Rejections to "Kill Request" Message.

Measurement point: As shown in Figure 3-43 A, this item is measured when BSC receives KILL Request from CBC regardless of the correctness of this message.

Formula: None.

Figure 3-43 Delete short message

CBC

KILL Request

REPORT Response

REJECT Response

BSC

A

C

B

A: Received "kill request" messages B: Reports to "kill request" message C: Rejections to "kill request" message




Received "Status-CBCH-Query" Messages Description: CBC sends STATUS CBCH QUERY Request to the BSC in order to obtain

the current loading of the CBCH of particular cells. After receiving this message and confirming its correctness, BSC will query the relative data in cell broadcast data library, and sends STATUS-CBCH-QUERY Response to CBC. If the received STATUS-CBCH-QUERY Request is incorrect, BSC will return REJECT Response. Related items: Rejections to "Status-CBCH-Query" Message and Reports to "Status-CBCH-Query" Message.

Measurement point: As shown in Figure 3-44 A, this item is measured when BSC receives STATUS-CBCH-QUERY request from CBC regardless of the correctness of this message.

Formula: None.

Figure 3-44 Query broadcast channel

CBC STATUS-CBCH-QUERY Request

STATUS-CBCH-QUERY Response

REJECT Response

BSC A

C

B

A: Received "status-CBCH-query" messages B: Reports to "status-CBCH-query" message C: Rejections to "status-CBCH-query" message

Received "Status-Message-Query" Messages Description: CBC sends a STATUS-MESSAGE-QUERY Request to the BSC in order to

obtain the current status of CB message for the cells referenced. After receiving this message and confirming its correctness, BSC will query the relative data in cell broadcast data library, and sends STATUS-MESSAGE-QUERY Response to CBC. If the received STATUS-MESSAGE-QUERY Request is incorrect, BSC will return REJECT Response. Related items: Reports to "Status-Message-Query" Message and Rejections to "Status-Message-Query" Message.

Measurement point: As shown in Figure 3-45 A, this item is measured when BSC receives STATUS- MESSAGE-QUERY Request from CBC regardless of the correctness of this message.

Formula: None.



Figure 3-45 Query the transmission of broadcast short message

CBC STATUS-MESSAGE-QUERY Request

STATUS-MESSAGE-QUERY Response

REJECT Response

BSC A

C

B

A: Received "status-message-query" messages B: Reports to "status-message-query" message C: Rejections to "status-message-query" message

Received "Set-DRX" Messages Description: DRX (Discontinuous Reception) mode can be configured in CBC so that

the MS can receive the CB message in DRX mode. In this mode, CBC sends SET-DRX Request to BSC. After receiving this message and confirming its correctness, BSC will set the next schedule message according to the parameter in the message, and send SET-DRX Response to CBC. If the received SET-DRX Request is incorrect, BSC will return REJECT Response. Related items: Reports to "Set-DRX" Message and Rejections to "Set-DRX" Message.

Measurement point: As shown in Figure 3-46 A, this item is measured when BSC receives SET-DRX Request from CBC regardless of the correctness of this message.

Formula: None.

Figure 3-46 Set DRX mode

CBC SET-DRX Request

SET-DRX Response

REJECT Response

BSC A

C

B

A: Received "set-DRX" messages B: Reports to "set-DRX" message C: Rejections to "set-DRX" message

Received "Reset Request" Messages Description: When CBC resetting the specified cell, it will send RESET Request to BSC.

After receiving this message and confirming its correctness, BSC will stop sending any message to the related cell, and clear the relative information in message library and cell broadcast table. If the status of Cell Broadcast Channel (CBCH) of the specified cell is




normal before resetting, BSC will return RESTART-INDICATION Request. If the status of CBCH is abnormal (e.g. cell failure or not installed, CBCH blocked), BSC will return FAILURE-INDICATION Request. If the received RESET Request is incorrect, BSC will return REJECT Response. Related items: Sent "Restart-Indication" Messages, Rejections to "Reset Request" Messages and Sent "Failure-Indication" Messages.

Measurement point: As shown in Figure 3-47 A, this item is measured when BSC receives RESET Request from CBC regardless of the status of cell CBCH.

Formula: None.

Figure 3-47 Reset cells

CBC BSC RESET Request

RESTART-INDICATION Request

FAILURE-INDICATION Request

REJECT Response

A B C D

A: Received "reset request" messages B: Successful reset C: Received "failure-indication" messages D: Unsuccessful reset

Reports to "Write-Replace" Message Description: CBC sends a WRITE-REPLACE message to the BSC when a new message

is created or a message already broadcast is modified. After receiving this message and confirming its correctness, BSC will judge whether it is a new message or a substitute. If it is a new message, it will store it in the message library. If it is a substitute message, it will delete the corresponding old message, and then store the new one in the message library. Next, BSC sends REPORT Response to CBC. Related items: Received "Write-Replace" Messages and Rejections to "Write-Replace" Message.

Measurement point: As shown in Figure 3-47 B, when BSC receives WRITE-REPLACE from CBC and the message is correct, it will send REPORT Response to CBC. This item is measured in this case.

Formula: None.

Rejections to "Write-Replace" Message Description: CBC sends a WRITE-REPLACE message to the BSC when a new message

is created or a message already broadcast is modified. After receiving this message and it is incorrect, BSC will return REJECT Response. Related items: Received "Write-Replace" Messages and Reports to "Write-Replace" Message.

Measurement point: As shown in Figure 3-47 C, when BSC receives WRITE-REPLACE from CBC and the message is incorrect, it will send REJECT Response to CBC. This item is measured in this case.

Formula: None.



Reports to "Kill Request" Message Description: CBC sends a KILL Request message to the BSC when a CB message sent

to the specified (one or multiple) cells is deleted. After receiving this message and confirming its correctness, BSC will delete it from the message library. Next, BSC sends REPORT Response to CBC. Related items: Received "Kill Request" Messages and Rejections to "Kill Request" Message.

Measurement point: As shown in Figure 3-47 B, when BSC receives KILL Request from CBC and the message is correct, it will send REPORT Response to CBC. This item is measured in this case.

Formula: None.

Rejections to "Kill Request" Message Description: CBC sends a KILL Request message to the BSC when a CB message sent

to the specified (one or multiple) cells is deleted. After receiving this message and it is incorrect, BSC will return REJECT Response. Related items: Received "Kill Request" Messages and Reports to "Kill Request" Message.

Measurement point: As shown in Figure 3-47 C, when BSC receives KILL Request from CBC and the message is incorrect, it will send REJECT Response to CBC. This item is measured in this case.

Formula: None.

Reports to "Status-CBCH-Query" Message Description: CBC sends STATUS CBCH QUERY Request to the BSC in order to obtain

the current loading of the CBCH of particular cells. After receiving this message and confirming its correctness, BSC will query the relative data in cell broadcast data table, and sends STATUS-CBCH-QUERY Response to CBC. Related items: Received "Status-CBCH-Query" Messages and Reports to "Status-Message-Query" Message.

Measurement point: As shown in Figure 3-47 B, when BSC receives STATUS-CBCH-QUERY Request from CBC and the message is correct, it will send REPORT Response to CBC. This item is measured in this case.

Formula: None.

Rejections to "Status-CBCH-Query" Message Description: CBC sends STATUS CBCH QUERY Request message to the BSC in order

to obtain the current loading of the CBCH of particular cells. If the received STATUS-CBCH-QUERY Request is incorrect, BSC will return REJECT Response. Related items: Received "Status-CBCH-Query" Messages and Rejections to "Status-CBCH-Query" Message.

Measurement point: As shown in Figure 3-47 C, when BSC receives STATUS-CBCH-QUERY Request from CBC and the message is incorrect, it will send REJECT Response to CBC. This item is measured in this case.

Formula: None.

Reports to "Status-Message-Query" Message Description: CBC sends a STATUS-MESSAGE-QUERY Request to the BSC in order to

obtain the current status of CB message for the cells referenced. After receiving this message and confirming its correctness, BSC will query the relative data in cell broadcast data table, and sends STATUS-MESSAGE-QUERY Response to CBC.




Related items: Received "Status-CBCH-Query" Messages and Rejections to "Status-Message-Query" Message.

Measurement point: As shown in Figure 3-47 B, when BSC receives STATUS- MESSAGE -QUERY Request from CBC and the message is correct, it will send REPORT Response to CBC. This item is measured in this case.

Formula: None.

Rejections to "Status-Message-Query" Message Description: CBC sends a STATUS-MESSAGE-QUERY Request message to the BSC in

order to obtain the current status of CB message for the cells referenced. If the received STATUS-MESSAGE-QUERY Request is incorrect, BSC will return REJECT Response. Related items: Reports to "Status-Message-Query" Message and Reports to "Status-Message-Query" Message.

Measurement point: As shown in Figure 3-47 C, when BSC receives STATUS- MESSAGE -QUERY Request from CBC and the message is incorrect, it will send REJECT Response to CBC. This item is measured in this case.

Formula: None.

Reports to "Set-DRX" Message Description: DRX (Discontinuous Reception) mode can be configured in CBC so that

the MS can receive the CB message in DRX mode. In this mode, CBC sends SET-DRX Request to BSC. After receiving this message and confirming its correctness, BSC will set the scheduling message of next transmission according to the parameter in the message, and send SET-DRX Response to CBC. If the received SET-DRX Request is incorrect, BSC will return REJECT Response. Related items: Received "Set-DRX" Messages and Rejections to "Set-DRX" Message.

Measurement point: As shown in Figure 3-47 B, when BSC receives SET-DRX Request from CBC and the message is correct, it will send SET-DRX Response to CBC. This item is measured in this case.

Formula: None.

Rejections to "Set-DRX" Message Description: DRX (Discontinuous Reception) mode can be configured in CBC so that

the MS can receive the CB message in DRX mode. In this mode, CBC sends SET-DRX Request to BSC. If the received SET-DRX Request is incorrect, BSC will return REJECT Response. Related items: Received "Set-DRX" Messages and Rejections to "Set-DRX" Message.

Measurement point: As shown in Figure 3-47 C, when BSC receives SET-DRX Request from CBC and the message is incorrect, it will send REJECT Response to CBC. This item is measured in this case.

Formula: None.

Sent "Restart-Indication" Messages Description: When CBC resetting the specified cell, it will send RESET Request to BSC.

After receiving this message and confirming its correctness, BSC will stop sending any message to the related cell, and clear the relative information in message library and cell broadcast table. If the status of Cell Broadcast Channel (CBCH) of the specified cell is normal before resetting, BSC will return RESTART-INDICATION Request. Related



items: Received "Reset Request" Messages, Rejections to "Reset Request" Messages and Sent "Failure-Indication" Messages.

Measurement point: Figure 3-47 B, when BSC receives RESET Request from CBC and the status of the cell CBCH is normal, it will send RESTART-INDICATION Request to CBC. This item is measured in this case.

Formula: None.

Rejections to "Reset Request" Messages Description: When CBC resetting the specified cell, it will send RESET Request to BSC.

If the received RESET Request is incorrect, BSC will return REJECT Response. Related items: Received "Reset Request" Messages, Sent "Restart-Indication" Messages and Sent "Failure-Indication" Messages.

Measurement point: Figure 3-47 D, when BSC receives RESET Request from CBC and the message is incorrect, it will send REJECT Response to CBC. This item is measured in this case.

Formula: None.

Sent "Failure-Indication" Messages Description: When resetting the specified cell, CBC will send RESET Request to BSC.

After receiving this message and confirming its correctness, BSC will stop sending any message to the related cell, and clear the relative information in message library and cell broadcast table. If the status of Cell Broadcast Channel (CBCH) of the specified cell is abnormal, BSC will return FAILURE-INDICATION Request. Related items: Received "Reset Request" Messages, Sent "Restart-Indication" Messages and Rejections to "Reset Request" Messages.

Measurement point: − As shown in Figure 3-47 C, when BSC receives RESET Request from CBC and the

message is correct while the status of CBCH is incorrect, it will send FAILURE-INDICATION Request to CBC. This item is measured in this case.

− This item is also measured when the links between BSC and Cell Broadcast DataBase (CDB) are all disconnected.

Formula: None.

CBCH Overload (Overflow) Description: BTS reports the information about load of CBCH to BSC with the message

CBCH Loading Indication, and requests BSC to implement corresponding flow control. According to the reported load type ("overflow" and "underflow"), BSC measures the times of overflow/underflow.

Measurement point: As shown in Figure 3-48 A, this item is measured when BSC receives CBCH Loading Indication from BTS, and load type is overflow.

Formula: None.




Figure 3-48 BTS reports CBCH overflow

BTS

CBCH Loading Indication

BSC

A(B)

A: CBCH overload (overflow) B: CBCH overload (underflow)

CBCH Overload (Underflow) Description: BTS reports the information about load of CBCH to BSC with the message

CBCH Loading Indication, and requests BSC to implement corresponding flow control. According to the reported load type ("overflow" and "underflow"), BSC measures the times of overflow/underflow.

Measurement point: As shown in Figure 3-48 B, this item is measured when BSC receives CBCH Loading Indication from BTS, and load type is underflow.

Formula: None.

Received "Write" Messages Description: CBC sends a WRITE-REPLACE message to the BSC when a new message

is created or a message already broadcast is modified. After receiving this message and confirming its correctness, BSC will judge whether it is a new message or a substitute. If it is a new message, it will store it in the message library. If it is a substitute message, it will delete the corresponding old message, and then store the new one in the message library. Next, BSC sends REPORT Response to CBC. If the WRITE-REPLACE message BSC receives is incorrect (not conforming to ETSI GSM 03.41), BSC will return REJECT Response. Related items: Reports to "Write-Replace" Message and Rejections to "Write" Messages.

Measurement point: As shown in Figure 3-49 A, this item is measured when BSC receives WRITE-REPLACE from CBC which contains WRITE within it and it is correct.

Formula: None.

Figure 3-49 Received "write" messages

CBC BSC

WRITE-REPLACE Request ( WRITE request )

REPORT Response

A

REJECT Response C

B

A: Received "write" messages B: Reports to "write" messages C: Rejections to "write" messages



Reports to "Write" Messages Description: CBC sends a WRITE-REPLACE message to the BSC when a new message

is created or a message already broadcast is modified. After receiving this message and confirming its correctness, BSC will judge whether it is a new message or a substitute. If it is a new message, it will store it in the message library. If it is a substitute message, it will delete the corresponding old message, and then store the new one in the message library. Next, BSC sends REPORT Response to CBC. Related items: Received "Write" Messages and Rejections to "Write" Messages.

Measurement point: As shown in Figure 3-49 B, when BSC receives WRITE-REPLACE from CBC which contains WRITE within it and it is correct, then BSC sends REPORT Response to CBC. In this case, the item is measured.

Formula: None.

Rejections to "Write" Messages Description: CBC sends a WRITE-REPLACE message to the BSC when a new message

is created or a message already broadcast is modified. After receiving this message and it is incorrect, BSC will return REJECT Response. Related items: Received "Write" Messages and Reports to "Write" Messages.

Measurement point: As shown in Figure 3-49 C, when BSC receives WRITE-REPLACE from CBC which contains WRITE within it and it is incorrect, BSC will return REJECT Response to CBC. In this case, the item is measured.

Formula: None.

Received "Replace" Messages Description: CBC sends a WRITE-REPLACE message to the BSC when a new message

is created or a message already broadcast is modified. After receiving this message and confirming its correctness, BSC will judge whether it is a new message or a substitute. If it is a new message, it will store it in the message library. If it is a substitute message, it will delete the corresponding old message, and then store the new one in the message library. Next, BSC sends REPORT Response to CBC. If the WRITE-REPLACE message BSC receives is incorrect (not conforming to ETSI GSM 03.41), BSC will return REJECT Response. Related items: Reports to "replace" Messages and Rejections to "Replace" Messages.

Measurement point: As shown in Figure 3-49 A, this item is measured when BSC receives WRITE-REPLACE from CBC which contains REPLACE within it and it is correct.

Formula: None.

Reports to "replace" Messages Description: CBC sends a WRITE-REPLACE message to the BSC when a new message

is created or a message already broadcast is modified. After receiving this message and confirming its correctness, BSC will judge whether it is a new message or a substitute. If it is a new message, it will store it in the message library. If it is a substitute message, it will delete the corresponding old message, and then store the new one in the message library. Next, BSC sends REPORT Response to CBC. Related items: Received "Replace" Messages and Rejections to "Replace" Messages.




Measurement point: As shown in Figure 3-49 B, when BSC receives WRITE-REPLACE from CBC which contains REPLACE within it and it is correct, then BSC sends REPORT Response to CBC. In this case, the item is measured.

Formula: None.

Rejections to "Replace" Messages Description: CBC sends a WRITE-REPLACE message to the BSC when a new message

is created or a message already broadcast is modified. After receiving this message and it is incorrect, BSC will return REJECT Response. Related items: Received "Replace" Messages and Reports to "replace" Messages.

Measurement point: As shown in Figure 3-49 C, when BSC receives WRITE-REPLACE from CBC which contains REPLACE within it and it is incorrect, BSC will return REJECT Response to CBC. In this case, the item is measured.

Formula: None.

Capacity of Message Library Description: After receiving a broadcast message from CBC, BSC will store the message

into message library. This item gives the percentage of number of stored messages in the library to the capacity of the library.

Measurement point: BSC gets the number of messages in message library every five minutes.

Formula: None.

Disconnected Times of BM 1 Description: The cell broadcast function is completed by CDB and each BM module.

CDB is the bridge of communication between CBC and BSC’s BM module, board GMEM responses for communication between BMs and CDB. During running, cases such as board broken will make the communication stop, then the messages can not be broadcast. This item gives the times of communication broken.

Measurement point: When the communication between CDB and BSC’s BM1 broken, this item is measured.

Formula: None.




Formula: None.


CDB is the bridge of communication between CBC and BSC’s BM module, board GMEM responses for communication between BMs and CDB. During running, cases



such as board broken will make the communication stop, then the messages can not be broadcast. This item gives the times of communication broken.


Formula: None.




Formula: None.




Formula: None.




Formula: None.




Formula: None.







Formula: None.

Disconnected Times of CBC Description: The cell broadcast function is completed by CDB and each BM module.


Measurement point: When the communication between CDB and CBC broken, this item is measured.

Formula: None.

3.7.3 BSC Cell Broadcast Measurement Function (Period) Table 3-11 lists all statistic items of BSC Cell Broadcast Measurement Function (Period). For detailed information of each items, please refer to 3.7.2 .

Table 3-11 Statistic items in BSC Cell Broadcast Measurement Function(Period)

No. Item name

1 Received "write-replace" messages in the period

2 Received "kill request" messages in the period

3 Received "status-CBCH-query" messages in the period

4 Received "status-message-query" messages in the period

5 Received "set-DRX" messages in the period

6 Received "reset request" messages in the period

7 Reports to "write-replace" message in the period

8 Rejections to "write-replace" message in the period

9 Reports to "kill request" message in the period

10 Rejections to "kill request" message in the period

11 Reports to "status-CBCH-query" message in the period

12 Rejections to "status-CBCH-query" message in the period

13 Reports to "status-message-query" message in the period

14 Rejections to "status-message-query" message in the period



No. Item name

15 Reports to "set-DRX" message in the period

16 Rejections to "set-DRX" message in the period

17 Sent "restart-indication" messages in the period

18 Rejections to "reset request" messages in the period

19 Sent "failure-indication" messages in the period

20 CBCH overload (overflow) in the period

21 CBCH overload (underflow) in the period

22 Received "write" messages in the period

23 Reports to "write" messages in the period

24 Rejections to "write" messages in the period

25 Received "replace" messages in the period

26 Reports to "replace" messages in the period

27 Rejections to "replace" messages in the period

28 Disconnected times of BM 1 in the period








36 Disconnected times of CBC in the period

3.7.4 BSC Cell Broadcast Measurement Function (Others) Table 3-12 lists all statistic items of BSC Cell Broadcast Measurement Function (Others).

Table 3-12 Statistic items in BSC Cell Broadcast Measurement Function (Others)

No. Item name

1 Configure Cell Number in the Period

2 Broadcasting Cell Number in the Period

3 Broadcasting Cell Rate in the Period




Configure Cell Number in the Period Description: BSC receives broadcast messages from CBC through CDB, then BSC

broadcast to the cells in it according to CBC’s broadcast schedule and the cell configured in BSC. This item gives the number of cells configured in BSC.

Measurement point: At the end of statistic period, the number of installed cells in BSC will be measured in this item.

Formula: None.

Broadcasting Cell Number in the Period Description: BSC receives broadcast messages from CBC through CDB, then BSC

broadcast to the cells in it according to CBC’s broadcast schedule and the cell configured in BSC. This item gives the number of cells broadcasted in BSC in the period.

Measurement point: When BSC broadcasts a message to a cell in it, this item is measured

Formula: None.

Broadcasting Cell Rate in the Period Description: This item is the ratio of the number of cells broadcasted in BSC in the

period to the number of all the installed cells in BSC. Measurement point: None. Formula: Broadcasting Cell Number in the period / Configure Cell Number in the period

3.8 MTP Measurement Function 3.8.1 General

In SS7 protocol system, SCCP (Signaling Connection Control Part) and MTP (Message Transfer Part) provide comprehensive network function for the application layer.

All the statistic items are listed in Table 3-13.

The measurement object of MTP Measurement Function is the signaling link managed by MTP service module of BSC. User can observe the operation of MTP processing part of A interface and analyze the operation of SS7 system so as to implement effective management over signaling network resources and evaluate the resource performance and effectiveness of resource utilization.

Table 3-13 Statistic items in MTP Measurement Function

No. Item name

1 Signaling Link In Service Duration

2 Signaling Link Unavailable Duration

3 Signaling Link Failure

4 Signaling Link Failure Duration



No. Item name

5 Inhibited Local Links

6 Local Link Inhibit Duration

7 Inhibited Remote Links

8 Remote Link Inhibit Duration

9 Remote Processor Failure

10 Remote Processor Failure Duration

11 Signaling Link Local Auto Rotate

12 Message Signaling Units (O)

13 Signaling Octets (O)

14 Signaling Link Sending Rate (%)

15 Message Signaling Units (I)

16 Signaling Octets (I)

17 Signaling Link Receiving Rate (%)

18 Signaling link In Congestion

19 Signaling Link Congestion Time

20 Lost Message Signaling Units due to Congestion

21 Transfer-Prohibited Signals (TFP) (I)

22 Percentage of TRX in Good Condition (%)

23 Ratio of Cell Usability (%)

24 Attempted TCH Re-Assignments

25 successful TCH Re-Assignments

26 TCH Call Drop (eMLPP)


Signaling Link In Service Duration Description: This item measures the duration of SS7 link in normal service. Measurement point: MTP service module of BSC checks the status of SS7 link once per

second. This item is measured when the status of the SS7 link is normal. Formula: none.




Signaling Link Unavailable Duration Description: This item measures the duration of SS7 link unavailable for various causes

including but not limited to local management inhibited, remote management inhibited and signaling link failure.

Measurement point: MTP service module of BSC checks the status of SS7 link once per second. This item is measured when the link is unavailable.

Formula: none.

Signaling Link Failure Description: This item measures the times of SS7 link out of service for various causes.

When a signaling link is out of service, its status is unavailable. But when a signaling link is unavailable, it is not necessarily out of service. For example, a signaling link can be unavailable due to remote management inhibited, but this link is not faulty.

Measurement point: This item is measured when SS7 is out of service. Formula: none.

Signaling Link Failure Duration Description: This item measures the duration of signaling link out of service due to link

failure. If the MTP service module of BSC receives the message indicating the failure of a remote processor via an SS7 link, and then this link is out of service due to failure, the measurement of the remote processor failure duration will be terminated, and only the signaling link failure duration will be measured.

Measurement point: MTP service module of BSC checks the status of SS7 link once per second. This item is measured when the link is out of service.

Formula: none.

Inhibited Local Links Description: This item measures the times of maintenance system successfully inhibiting

the SS7 link. In this occasion, the status of the SS7 link is unavailable. Measurement point: This item is measured when the SS7 link is successfully inhibited by

the maintenance system. Formula: none.

Local Link Inhibit Duration Description: This item measures the duration of signaling link in the status of local

management inhibited after the SS7 link is successfully inhibited by maintenance system.

Measurement point: MTP service module of BSC checks the status of SS7 link once per second. This item is measured when the link is in the status of local management inhibited.

Formula: none.

Inhibited Remote Links Description: This item measures the times of remote signaling point successfully

inhibiting SS7 link. In this case, the status of SS7 link is unavailable. Measurement point: This item is measured when the SS7 link is successfully inhibited by

a remote signaling point.



Formula: none.

Remote Link Inhibit Duration Description: This item measures the duration of signaling link in the status of remote

management inhibited after the SS7 link is successfully inhibited by remote signaling point.

Measurement point: MTP service module of BSC checks the status of SS7 link once per second. This item is measured when the link is in the status of remote management inhibited.

Formula: none.

Remote Processor Failure Description: This item measures the times of MTP service module of BSC receiving the

message indicating remote processor failure via an SS7 link. In this occasion, the status of SS7 is unavailable.

Measurement point: This item is measured when MTP service module of BSC receives the message indicating remote processor failure.

Formula: none.

Remote Processor Failure Duration Description: This item measures the duration of signaling link in the status of

unavailable due to remote processor failure after MTP service module of BSC receives the message indicating remote processor failure.

Measurement point: MTP service module of BSC checks the status of SS7 link once per second. This item is measured when the link unavailable due to remote processor failure.

Formula: none.

Signaling Link Local Auto Rotate Description: This item measures the times of MTP service module of BSC switching the

service from one SS7 link to another SS7 link when the status of the SS7 link changes from available to unavailable.

Measurement point: This item is measured when MTP service module of BSC initiates service switching on SS7 links.

Formula: none.

Message Signaling Units (O) Description: This item measures the number of message signal units transmitted by MTP

service module of BSC via an SS7 link. Measurement point: This item is measured when MTP service module of BSC sends

message signal unit via an SS7 link. Formula: none.

Signaling Octets (O) Description: This item measures the number of bytes occupied by Signaling Information

Field (SIF) and Service Information Octet (SIO) in the message signal unit transmitted by MTP service module of BSC via an SS7 link.




Measurement point: This item is measured when MTP service module of BSC transmits message signal unit via an SS7 link.

Formula: none.

Signaling Link Sending Rate (%) Description: This item measures the percentage of message signal units sent by MTP

service module of BSC via an SS7 link to the bearing capability (bandwidth) of a signaling link. The bearing capability of a signaling link is 8k Byte/s, i.e. 8 % 1024 = 8192 (Byte/s). Each message signal unit contains message contents (SIF + SIO) of several bytes and other information of 6 bytes. Therefore the bytes of message signal units transmitted via a signaling link can be calculated with the formula: "Signaling octets (O) + Message signaling units (O) % 6".

Measurement point: none. Formula: (Signaling octets (O) + Message signaling units (O) % 6) / (8192 %

measurement cycle(second))

Message Signaling Units (I) Description: This item measures the number of message signal units received by MTP

service module of BSC via an SS7 link. Measurement point: This item is measured when MTP service module of BSC receives

message signal unit via an SS7 link. Formula: none.

Signaling Octets (I) Description: This item measures the number of bytes occupied by Signaling Information

Field (SIF) and Service Information Octet (SIO) in the message signal unit received by MTP service module of BSC via an SS7 link.

Measurement point: This item is measured when MTP service module of BSC receives message signal unit via an SS7 link.

Formula: none.

Signaling Link Receiving Rate (%) Description: This item measures the percentage of message signal units received by MTP

service module of BSC via an SS7 link to the bearing capability (bandwidth) of signaling link. The bearing capability of signaling link is 8k Byte/s, i.e. 8 % 1024 = 8192 (Byte/s). Each message signal unit contains message contents (SIF + SIO) of several bytes and other information of 6 bytes. Therefore the bytes of message signal units received via a signaling link can be calculated with the formula: "Signaling octets (I) + Message signaling units (I) % 6".

Measurement point: none. Formula: (Signaling octets (I) + Message signaling units (I) % 6) / (8192 % measurement

cycle(second))

Signaling link In Congestion Description: This item measures the times of the number of messages in the sending

buffer to be sent from L3 of MTP service module of BSC exceeding congestion threshold.



Measurement point: This item is measured when the number of messages in the sending buffer to be sent from L3 of MTP service module of BSC exceeds congestion threshold.

Formula: none.

Signaling Link Congestion Time Description: This item measures the duration of the number of messages in the sending

buffer sent from L3 of MTP service module of BSC exceeding congestion threshold. Measurement point: MTP service module of BSC checks the status of SS7 link once per

second. This item is measured when the number of messages in the buffer to be sent from L3 of MTP service module of BSC exceeds congestion threshold.

Formula: none.

Lost Message Signaling Units due to Congestion Description: This item measures the number of message signal units discarded when the

number of messages in the sending buffer to be sent from L3 of MTP service module of BSC exceeding congestion threshold.

Measurement point: This item is measured when the number of messages in the sending buffer to be sent from L3 of MTP service module of BSC exceeds congestion threshold and the message signal units is to be discarded.

Formula: none.

Transfer-Prohibited Signals (TFP) (I) Description: This item measures the times of MTP service module of BSC receiving

TransFer-Prohibited (TFP) message via an SS7 link. Measurement point: This item is measured when MTP service module of BSC receives

TFP message via an SS7 link. Formula: none.

Percentage of TRX in Good Condition (%) Description: This item reflects the percentage of available TRXs to configured TRXs.. Measurement point: Omitted. Formula: Sum of available TRX in the BSC / Sum of configured TRX in the BSC

Ratio of Cell Usability (%) Description: This item reflects the percentage of unusable time of the cell to the statistic

cycle. Measurement point: Omitted. Formula: 1-unusable time of the cell (s) / Statistic cycle (s).

Attempted TCH Re-Assignments Description: This item reflects the times of the re-assignment in the cell. Measurement point: send re-assignment TCH CHANNEL ACTIVATION active. Formula: None.




successful TCH Re-Assignments Description: This item reflects the successful times of the re-assignment in the cell. Measurement point: receive UM re-assignment ASSIGNMENT COMPLETE message. Formula: None.

TCH Call Drop (eMLPP) Description: This item reflects the TCH drop times because of eMLPP in the cell. Measurement point: release the lower priority subscriber. Formula: None.

Technology

01 03 traffic statistic items