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EDGE and GPRS KeyPerformance Indicators
DN7032527Issue 4-1 en
# Nokia Corporation 1 (49)
BSC3120Nokia GSM/EDGE BSS, Rel. BSS12, SystemDocumentation, v.1
The information in this document is subject to change without notice and describes only theproduct defined in the introduction of this documentation. This document is intended for the useof Nokia's customers only for the purposes of the agreement under which the document issubmitted, and no part of it may be reproduced or transmitted in any form or means without theprior written permission of Nokia. The document has been prepared to be used by professionaland properly trained personnel, and the customer assumes full responsibility when using it.Nokia welcomes customer comments as part of the process of continuous development andimprovement of the documentation.
The information or statements given in this document concerning the suitability, capacity, orperformance of the mentioned hardware or software products cannot be considered binding butshall be defined in the agreement made between Nokia and the customer. However, Nokia hasmade all reasonable efforts to ensure that the instructions contained in the document areadequate and free of material errors and omissions. Nokia will, if necessary, explain issueswhich may not be covered by the document.
Nokia's liability for any errors in the document is limited to the documentary correction of errors.NOKIA WILL NOT BE RESPONSIBLE IN ANY EVENT FOR ERRORS IN THIS DOCUMENTOR FOR ANY DAMAGES, INCIDENTAL OR CONSEQUENTIAL (INCLUDING MONETARYLOSSES), that might arise from the use of this document or the information in it.
This document and the product it describes are considered protected by copyright according tothe applicable laws.
NOKIA logo is a registered trademark of Nokia Corporation.
Other product names mentioned in this document may be trademarks of their respectivecompanies, and they are mentioned for identification purposes only.
Copyright © Nokia Corporation 2007. All rights reserved.
2 (49) # Nokia Corporation DN7032527Issue 4-1 en
EDGE and GPRS Key Performance Indicators
Contents
Contents 3
Summary of changes 5
1 EDGE and GPRS key performance indicators (KPIs) 9
2 EDGE and GPRS KPI categories 11
3 Network usage KPIs 13
4 Congestion KPIs 234.1 PDTCH congestion KPIs 234.2 Abis congestion KPIs 244.3 PCU congestion KPIs 254.4 Gb congestion KPIs 27
5 PDTCH quality KPIs 29
6 Mobility KPIs 35
7 Availability KPIs 37
8 User experience KPIs 39
9 Reference for used formulas 41
10 Traffic monitoring principles 47
DN7032527Issue 4-1 en
# Nokia Corporation 3 (49)
Contents
4 (49) # Nokia Corporation DN7032527Issue 4-1 en
EDGE and GPRS Key Performance Indicators
Summary of changes
Changes between document issues are cumulative. Therefore, the latest documentissue contains all changes made to previous issues.
Changes made between issues 4-1 and 4-0
Changes made between issues 4-1 and 4-0 lists the main changes made to thedocument after the Nokia GSM/EDGE BSS, Rel. BSS12, System Documentationpilot release. The following changes have been made:
. Use section under Downlink multislot soft blocking, S10.5 (blck_33) hasbeen modified.
Changes made between issues 4-0 and 3-2
Chapter Quality KPIs has been renamed to PDTCH quality KPIs.
Chapter Traffic monitoring principles has been added to the document. In theearlier releases this chapter was part of the EDGE dimensioning documents.
Information on Enhanced Quality of Service (EQoS) has been removed because itis not supported in BSS12.
The following KPIs have been added:
. dtm_3
. dtm_4
. dtm_5
. trf_170
. trf_171a
. trf_202a
. trf_242
. tbf_61
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# Nokia Corporation 5 (49)
Summary of changes
. tbf_65
. llc_3a
. llc_4a
. tbf_66
. nccr_1
. nccr_13
The following KPIs have been removed:
. trf_231
. trf_232
. llc_3
Changes made between issues 3-2 and 3-0
The key performance indicators (KPIs) have been updated to BSS11.5, version 3level.
The following KPI has been removed:
. tbf_36a
The following KPIs have been added:
. ava_68
. ava_71
. ava_72
. dap_9
. llc_3
. tbf_64
. trf_161h
. trf_162f
. trf_204
. trf_203b
6 (49) # Nokia Corporation DN7032527Issue 4-1 en
EDGE and GPRS Key Performance Indicators
. trf_205b
. trf_208b
The version of the following KPIs has been changed:
Old version New version
trf_213b trf_213c
trf_212b trf_212c
trf_214b trf_214a
trf_237c trf_237b
trf_235a trf_235b
trf_233b trf_233c
trf_234a trf_234
dap_7b dap_7a
Accuracy information has been added to formulas trf_214a and trf_237b inNetwork usage KPIs.
GPRS has been changed to EGPRS in the name of formulas trf_236 and trf_234in Quality KPIs.
Availability KPIs and User experience KPIs have been added.
In addition, the naming conventions have been unified.
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Summary of changes
8 (49) # Nokia Corporation DN7032527Issue 4-1 en
EDGE and GPRS Key Performance Indicators
1 EDGE and GPRS key performanceindicators (KPIs)
These are the Nokia recommendations for the EDGE and GPRS key performanceindicators (KPIs). KPIs for CS-3 and CS-4 are also included.
These definitions are subject to change. Nokia improves the definitions and thelist of KPIs according to received feedback and results from testing and fieldoperations.
A KPI is a value that presents some vital information about the network. TheKPIs are mapped directly from performance indicators (PIs), a formula of severalPIs, or directly from network counters.
Nokia has divided the EDGE and GPRS KPIs into the following categories:
. Network usage
. Congestion
. Quality
. Mobility
. Availability
. User experience
Related topics
. EDGE and GPRS KPI categories
. Network usage KPIs
. Congestion KPIs
. Quality KPIs
. Mobility KPIs
. Availability KPIs
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EDGE and GPRS key performance indicators (KPIs)
. User experience KPIs
. Reference for used formulas
10 (49) # Nokia Corporation DN7032527Issue 4-1 en
EDGE and GPRS Key Performance Indicators
2 EDGE and GPRS KPI categories
Table KPI groups and formula names lists the key performance indicator (KPI)groups.
The last letter after the formula ID number is for version control. When smallimprovements to the formula are made, the last letter is incremented but theformula number remains unchanged.
Table 1. KPI groups and formula names
KPI group Description Formula ID
Network usage DownlinkGPRSRLC payload trf_213c
Uplink GPRS RLC payload trf_212c
Downlink EGPRS RLC payload trf_215a
Uplink EGPRS RLC payload trf_214a
DTM PS payload ratio dtm_3
PSerlangs trf_237b
Relative share of PS Erlangs trf_242
Downlink GPRS erlangs trf_208b
Uplink GPRS erlangs trf_205b
Downlink EGPRS erlangs trf_162f
Uplink EGPRS erlangs trf_161h
Uplink signalling TBFs usage ratio tbf_61
Share of EDGE requests tbf_65
PDTCH congestion Downlink multislot allocationblocking
tbf_16
Downlink multislot soft blocking blck_33
Downlink TBFs per timeslot tbf_38c
Abis congestion Inadequate EDAP resources indownlink
dap_7a
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EDGE and GPRS KPI categories
Table 1. KPI groups and formula names (cont.)
PCU congestion Territory upgrade rejections due toa lack of PCU capacity
blck_32
Downlink MCS selection limited byPCU
dap_9
Gb congestion Downlink Gb load frl_8a
PDTCH quality Downlink GPRS RLC throughput trf_235b
Uplink GPRS RLC throughput trf_233c
Downlink EGPRS RLC throughput trf_236
Uplink EGPRS RLC throughput trf_234
TBF establishment failure ratio tbf_66
Mobility Downlink flush per minute tbf_64
NCCR success ratio nccr_13
Availability Data service availability ratio ava_68
User experience LLC throughput for 4-tsl EDGEMSs
llc_3a
LLC throughput for GPRS MSs (foreach QoS class)
llc_4a
Most of the KPIs are combined to be common for one BTS. Abis, PCU, and Gbcongestion KPIs are related to the Abis interface (Dynamic Abis), BSC, and Gbinterface respectively. However, the BTS KPIs can be summed up (that is, overone BSC) to obtain the corresponding KPIs at the BSC level.
12 (49) # Nokia Corporation DN7032527Issue 4-1 en
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3 Network usage KPIsDownlink GPRS RLC payload, S9 (trf_213c)
Use:
Indicates all GPRS payload data in downlink.
Formula (NetAct names):
All GPRS DL payload data (kbytes) =
sum(a.rlc_data_blocks_dl_cs1 x 20
+ a.rlc_data_blocks_dl_cs2 x 30
+ sum over MCS-11 (b.dl_rlc_blocks_in_ack_mode +
b.dl_rlc_blocks_in_unack_mode) x 36
+ sum over MCS-12 (b.dl_rlc_blocks_in_ack_mode +
b.dl_rlc_blocks_in_unack_mode) x 50
)/1024
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit:
kbytes
Uplink GPRS RLC payload, S9 (trf_212c)
Use:
Indicates all GPRS payload data in uplink.
Formula (NetAct names):
All GPRS UL payload data (kbytes) =
sum(a.rlc_data_blocks_ul_cs1 x 20
+ a.rlc_data_blocks_ul_cs2 x 30
+ sum over MCS-11 (b.ul_rlc_blocks_in_ack_mode +
b.ul_rlc_blocks_in_unack_mode) x 36
+ sum over MCS-12 (b.ul_rlc_blocks_in_ack_mode +
b.ul_rlc_blocks_in_unack_mode) x 50
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Network usage KPIs
)/1024
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit:
kbytes
Downlink EGPRS RLC payload, S10.5 (trf_215a)
Use:
Indicates all EGPRS payload data in downlink.
Formula:
(sum over MCS-1 (xx) x 22 +
sum over MCS-2 (xx) x 28 +
sum over MCS-3 (xx) x 37 +
sum over MCS-4 (xx) x 44 +
sum over MCS-5 (xx) x 56 +
sum over MCS-6 (xx) x 74 +
sum over MCS-7 (xx/2) x 112 +
sum over MCS-8 (xx/2) x 136 +
sum over MCS-9 (xx/2) x 148)
/1024
where xx =
(DL_RLC_BLOCKS_IN_ACK_MODE + DL_RLC_BLOCKS_IN_UNACK_MODE)
Counters from table(s):
p_nbsc_coding_scheme
Unit:
kbytes
Uplink EGPRS RLC payload, S10.5 (trf_214a)
Use:
Indicates all EGPRS payload data in uplink.
Note
This KPI calculates UL payload inaccurately prior to S11.5 CD4.0. Accuratecalculation is available from S11.5 CD4.0 onwards.
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Formula (NetAct names):
(sum over MCS-1 (xx) x 22 +
sum over MCS-2 (xx) x 28 +
sum over MCS-3 (xx) x 37 +
sum over MCS-4 (xx) x 44 +
sum over MCS-5 (xx) x 56 +
sum over MCS-6 (xx) x 74 +
sum over MCS-7 (xx/2) x 112 +
sum over MCS-8 (xx/2) x 136 +
sum over MCS-9 (xx/2) x 148))
)/1024
where xx =
(UL_RLC_BLOCKS_IN_ACK_MODE + UL_RLC_BLOCKS_IN_UNACK_MODE)
Counters from table(s):
p_nbsc_coding_scheme
Unit:
kbytes
DTM PS payload ratio, S12 (dtm_3)
Use:
Ratio of DTM PS payload (UL plus DL) to all PS payload.
Formula (NetAct names):
(dtm_4 + dtm_5) / (trf_212c + trf_213c + trf_214a + trf_215a)
Unit:
%
PS erlangs, S10.5 (trf_237b)
Use:
Detects the maximum amount of PS data traffic during the measurement period.
Note
This KPI calculates UL payload inaccurately prior to S11.5 CD4.0. Accuratecalculation is available from S11.5 CD4.0 onwards.
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Network usage KPIs
Formula (NetAct names):
PS Erlangs = max(UL PS Erlangs, DL PS Erlangs) =
Max((a.rlc_data_blocks_ul_cs1
+ a.rlc_data_blocks_ul_cs2
+ a.BAD_FRAME_IND_UL_CS1
+ a.BAD_FRAME_IND_UL_CS2
+ a.BAD_FRAME_IND_UL_UNACK
+ a.rlc_mac_cntrl_blocks_ul
+ a.ignor_rlc_data_bl_ul_due_bsn x X
+ sum over MCS0..6 of (b.ul_rlc_blocks_in_ack_mode +
b.ul_rlc_blocks_in_unack_mode +
b.bad_rlc_valid_hdr_ul_ack +
b.bad_rlc_valid_hdr_ul_unack +
b.bad_rlc_bad_hdr_ul_ack +
b.bad_rlc_bad_hdr_ul_unack)
+ sum over MCS7..9 of (b.ul_rlc_blocks_in_ack_mode +
b.ul_rlc_blocks_in_unack_mode +
b.bad_rlc_valid_hdr_ul_ack +
b.bad_rlc_valid_hdr_ul_unack +
b.bad_rlc_bad_hdr_ul_ack +
b.bad_rlc_bad_hdr_ul_unack)/2)
+ sum over MCS-11..12 of (b.ul_rlc_blocks_in_ack_mode +
b.bad_rlc_valid_hdr_ul_unack +
b.bad_rlc_valid_hdr_ul_ack +
b.bad_rlc_bad_hdr_ul_ack +
b.bad_rlc_bad_hdr_ul_unack +
b.ul_rlc_blocks_in_unack_mode)
------------------------------------------------------------------
, period_duration x 60 x 50
(a.rlc_data_blocks_dl_cs1 +
a.rlc_data_blocks_dl_cs2 +
a.retra_rlc_data_blocks_dl_cs1 +
a.retra_rlc_data_blocks_dl_cs2 +
a.rlc_mac_cntrl_blocks_dl
+ sum over mcs1..6 of (b.dl_rlc_blocks_in_ack_mode +
b.dl_rlc_blocks_in_unack_mode +
b.retrans_rlc_data_blocks_dl)
+ sum over mcs7..9 of (b.dl_rlc_blocks_in_ack_mode +
b.dl_rlc_blocks_in_unack_mode +
b.retrans_rlc_data_blocks_dl)/2)
+ sum over MCS-11..12 of (b.dl_rlc_blocks_in_ack_mode +
b.dl_rlc_blocks_in_unack_mode +
b.retrans_rlc_data_blocks_dl))
-------------------------------------------------------------------
period_duration x 60 x 50)
Where X = 0.5 x A/(A+B) + 1 x B/(A+B)
A = sum over MCS7...9 of (b.ul_rlc_blocks_in_ack_mode +
b.ul_rlc_blocks_in_unack_mode)
B = (sum over MCS1...6 of (b.ul_rlc_blocks_in_ack_mode +
b.ul_rlc_blocks_in_unack_mode))
+ a.rlc_data_blocks_ul_cs1 + a.rlc_data_blocks_ul_cs2
+ sum over MCS-11..12 of (b.ul_rlc_blocks_in_ack_mode +
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b.ul_rlc_blocks_in_unack_mode)
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit:
Erlangs
Relative share of PS Erlangs, S12 (trf_242)
Use:
Indicates the ratio of PS traffic in erlangs compared to all erlangs (PS + CS).
Formula (NetAct names):
trf_237b
100 * ----------------
trf_237b + trf_171a
Unit:
%
Downlink GPRS traffic, S11.5 (trf_208b)
Use:
Indicates the amount of resources (timeslots) the GPRS traffic (excluding EDGEtraffic) consumes, on average, during the period. This information is useful, forexample, in estimating the need for capacity extension. 50 blocks/sec/TSL is usedto estimate the timeslots.
OSS4.0 is needed to collect all counters.
Formula (logical):
Actual DL data throughput (blocks)
------------------------------------------------------------- =
nbr of blocks equivalent to 1 tsl full use in each BTS of area
Formula (NetAct names):
sum(a.rlc_data_blocks_dl_cs1
+ a.rlc_data_blocks_dl_cs2
+ a.retra_rlc_data_blocks_dl_cs1
+ a.retra_rlc_data_blocks_dl_cs2)
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+ sum over MCS-11..12 (b.dl_rlc_blocks_in_ack_mode
+ b.dl_rlc_blocks_in_unack_mode
+ b.retrans_rlc_data_blocks_dl)
+ (a.rlc_mac_cntrl_blocks_dl - a.egprs_dl_ctrl_blocks)
------------------------------------------------------
sum(period_duration*60)*50; 50 blocks /sec /tsl
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit:
TSL or erlang
Uplink GPRS traffic, S11.5 (trf_205b)
Use:
Indicates the amount of resources (timeslots) the GPRS traffic (excluding EDGEtraffic) consumes, on average, during the period. This information is useful, forexample, in estimating the need for capacity extension. 50 blocks/sec/TSL is usedto estimate the timeslots.
OSS4.0 is needed to collect all counters.
Formula (NetAct names):
Actual UL data throughput (blocks)
------------------------------------------------------------- =
nbr of blocks equivalent to 1 tsl full use in each BTS of area
sum(a.rlc_data_blocks_ul_cs1
+ a.rlc_data_blocks_ul_cs2
+ a.bad_frame_ind_ul_cs1
+ a.bad_frame_ind_ul_cs2
+ a.bad_frame_ind_ul_unack
+ sum over MCS-11..12 (b.ul_rlc_blocks_in_ack_mode
+ b.ul_rlc_blocks_in_unack_mode
+ b.bad_rlc_valid_hdr_ul_unack
+ b.bad_rlc_bad_hdr_ul_unack
+ b.bad_rlc_valid_hdr_ul_ack
+ b.bad_rlc_bad_hdr_ul_ack)
+ (a.rlc_mac_cntrl_blocks_ul - a.egprs_ul_ctrl_blocks)
+ [ignor rlc data bl ul due bsn gprs])
----------------------------------------------------
sum(period_duration*60)*50 ; 50 blocks /sec /tsl
[ignor rlc data bl ul due bsn gprs] =
trf_203b
a.ignor_rlc_data_bl_ul_due_bsn * -----------------
trf_203b + trf_204
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Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit:
TSL or erlang
Downlink EGPRS erlangs, S11.5 (trf_162f)
Use:
Indicates the amount of resources (timeslots) the DL EGPRS traffic dataconsumes. This information is useful, for example, in estimating the need forcapacity extension.
For area level, this formula should be first collected for all BTSs in the area.Then, the results should be summed up for the area.
OSS4.0 is needed to collect all counters.
Formula (logical):
Actual DL data throughput (blocks)
------------------------------------------------------------- =
nbr of blocks equivalent to 1 tsl full use in each BTS of area
Formula (NetAct names):
sum over mcs1..6 of (
a.dl_rlc_blocks_in_ack_mode
+ a.retrans_rlc_data_blocks_dl
+ a.dl_rlc_blocks_in_unack_mode
)
+ sum over mcs7..9 of (
a.dl_rlc_blocks_in_ack_mode
+ a.retrans_rlc_data_blocks_dl
+ a.dl_rlc_blocks_in_unack_mode
)/2
+ (b.egprs_dl_ctrl_blocks)
------------------------------------------------
sum(b.period_duration*60)*50 ;50 blocks/sec/tsl
Counters from table(s):
a = p_nsbc_coding_scheme
b = p_nsbc_packet_control_unit
Unit:
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Network usage KPIs
TSL or erlang
Uplink EGPRS erlangs, S11.5 (trf_161h)
Use:
Indicates the amount of resources (timeslots) the EGPRS traffic data consumes,on average, during the period. This information is useful, for example, inestimating the need for capacity extension. 50 blocks/sec/TSL is used to estimatethe timeslots.
For area level, this formula should be first collected for all BTSs in the area.Then, the results should be summed up for the area.
OSS4.0 is needed to collect all counters.
Formula (logical):
actual UL data throughput (blocks)
-------------------------------------------------------------- =
nbr of blocks equivalent to 1 tsl full use in each BTS of area
Formula (NetAct names):
sum over MCS0..6 of
( a.ul_rlc_blocks_in_ack_mode
+ a.BAD_RLC_VALID_HDR_UL_ACK
+ a.bad_rlc_valid_hdr_ul_unack
+ a.ul_rlc_blocks_in_unack_mode
+ a.bad_rlc_bad_hdr_ul_ack
+ a.bad_rlc_bad_hdr_ul_unack)
+ sum over MCS7..9 of
( a.ul_rlc_blocks_in_ack_mode
+ a.bad_rlc_bad_hdr_ul_ack
+ a.bad_rlc_bad_hdr_ul_unack
+ a.BAD_RLC_VALID_HDR_UL_ACK
+ a.bad_rlc_valid_hdr_ul_unack
+ a.ul_rlc_blocks_in_unack_mode)/2
+ egprs_ul_ctrl_blocks
+ [ignor rlc radio bl ul due bsn egprs]
-------------------------------------------------------------
avg(period_duration*60) x count( distinct period_start_time)
x 50 ; 50 blocks/sec/tsl
[ignor rlc radio bl ul due bsn egprs] =
trf_204
ignor_rlc_data_bl_ul_due_bsn x X x ------------------
trf_203b + trf_204
Where X = 0.5 x A/(A+B) + 1 x B/(A+B)
A = sum over MCS7...9 of (a.ul_rlc_blocks_in_ack_mode +
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a.ul_rlc_blocks_in_unack_mode)
B = sum over MCS1...6 of (a.ul_rlc_blocks_in_ack_mode +
a.ul_rlc_blocks_in_unack_mode)
Counters from table(s):
a = p_nbsc_coding_scheme
b = p_nbsc_packet_control_unit
Unit:
TSL or erlang
Uplink signalling TBFs usage ratio, S12 (tbf_61)
Use:
Indicates the percentage of signalling TBFs from the total of all UL TBFs.
Formula:
Sum(ul_tbf_for_signalling)
100* --------------------------------------------
sum(ul_tbf_for_signalling + ul_tbf_for_data)
Unit:
%
Share of EDGE requests, S12 (tbf_65)
Use:
Shows the ratio of timeslot requests where EDGE resources are required. Worksalso if EDGE is not activated in the network.
Formula:
sum(req_1_tsl_ul_for_egprs_ms
+ req_2_tsl_ul_for_egprs_ms
+ req_3_tsl_ul_for_egprs_ms
+ req_4_tsl_ul_for_egprs_ms
+ req_5_tsl_ul_for_egprs_ms
+ req_6_tsl_ul_for_egprs_ms
+ req_7_tsl_ul_for_egprs_ms
+ req_8_tsl_ul_for_egprs_ms
+ req_1_tsl_dl_for_egprs_ms
+ req_2_tsl_dl_for_egprs_ms
+ req_3_tsl_dl_for_egprs_ms
+ req_4_tsl_dl_for_egprs_ms
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+ req_5_tsl_dl_for_egprs_ms
+ req_6_tsl_dl_for_egprs_ms
+ req_7_tsl_dl_for_egprs_ms
+ req_8_tsl_dl_for_egprs_ms)
100 * ------------------------------
sum(req_1_tsl_ul
+ req_2_tsl_ul
+ req_3_tsl_ul
+ req_4_tsl_ul
+ req_5_tsl_ul
+ req_6_tsl_ul
+ req_7_tsl_ul
+ req_8_tsl_ul
+ req_1_tsl_dl
+ req_2_tsl_dl
+ req_3_tsl_dl
+ req_4_tsl_dl
+ req_5_tsl_dl
+ req_6_tsl_dl
+ req_7_tsl_dl
+ req_8_tsl_dl)
Unit:
%
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4 Congestion KPIs
4.1 PDTCH congestion KPIs
Downlink multislot allocation blocking, S9 (tbf_16)
Use:
If blocking happens regularly, either the territory (CS traffic low) or TCHcapacity (CS traffic high) needs to be expanded.
Note
If the statistics show that there is blocking but no upgrade requests yet, thereason may be that the territory is smaller than defined in the default settings(CS use). The PCU will not make an upgrade request. This is because theCSW side returns the default channels back to the PS territory as soon as theCSW load allows this.
Formula:
sum(NO_RADIO_RES_AVA_DL_TBF)
100 x -------------------------------------------------------- %
sum(req_1_TSL_DL + req_2_TSL_DL + req_3_TSL_DL
+ req_4_TSL_DL + req_5_8_TSL_DL)
Counters from table(s):
p_nbsc_packet_control_unit
Downlink multislot soft blocking, S10.5 (blck_33)
Use:
Indicates the ratio of unserved timeslots requests to all requests in downlink. IfHigh Multislot Classes (HMC) has been activated in the network, formulablck_33a (100-msl_6a) is recommended to be used.
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Formula:
100 - msl_6
Counters from table(s):
p_nbsc_packet_control_unit
For the msl_6 definition, see Ratio of served GPRS DL TSL requests, S9 (msl_6).
Downlink TBFs per timeslot, S9 (tbf_38c)
Use:
Indicates how many downlink TBFs there are, on average, per timeslot.
Formula:
sum(aver_tbfs_per_tsl_dl_sum)
-----------------------------------
sum(aver_tbfs_per_tsl_dl_den) x 100
Counters from table(s):
p_nbsc_packet_control_unit
4.2 Abis congestion KPIs
Inadequate EDAP resources in downlink, S11 (dap_7a)
Use:
Indicates time per kilobytes when the available downlink EDAP resources areinadequate.
Indicates the time per gigabytes when the available downlink EDAP resources areinadequate because of the size of the EDAP. The formula may not give correctvalues if:
. the object aggregation level is smaller than the BSC level, and
. one or more BTSs in the area has more than one dynamic Abis poolconnected.
Formula (NetAct names):
Sum (DL_indadeq_time_minutes) /
Sum (DL GPRS payload_Gbyte + DL EGPRS payload_Gbyte)
=
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sum( a.dl_tbfs_with_inadeq_edap_res -
a.dl_mcs_limited_by_pcu) / (50 x 60)
-------------------------------------
sum over BTS with EGENA = Y
( b.rlc_data_blocks_dl_cs1 x 20
+ b.rlc_data_blocks_dl_cs2 x 30
+ sum over MCS-1 (xx) x 22
+ sum over MCS-2 (xx) x 28
+ sum over MCS-3 (xx) x 37
+ sum over MCS-4 (xx) x 44
+ sum over MCS-5 (xx) x 56
+ sum over MCS-6 (xx) x 74
+ sum over MCS-7 (xx/2) x112
+ sum over MCS-8 (xx/2) x 136
+ sum over MCS-9 (xx/2) x 148
+ sum over MCS-11(xx) x 36
+ sum over MCS-12(xx) x 50
) / (1024 x 1024 x 1024)
where xx = (c.dl_rlc_blocks_in_ack_mode
+ c.dl_rlc_blocks_in_unack_mode)
Counters from table(s):
a = p_nbsc_dynamic_abis
b = p_nbsc_packet_control_unit
c = p_nbsc_coding_scheme
Unit:
min/GB
Note that minutes here refer to radio timeslot minutes, not to end user minutes.
4.3 PCU congestion KPIs
Territory upgrade rejections due to a lack of PCU capacity, S9 (blck_32)
Use:
Indicates the ratio of territory upgrade requests that result in rejection because ofPCU capacity.
Formula:
sum(gprs_ter_ug_rej_due_lack_pcu)
100 x ----------------------------------%
sum(gprs_ter_upgrd_req)
Counters from table(s):
p_nbsc_traffic
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Downlink MCS selection limited by PCU, S11.5 (dap_9)
Use:
Indicates the time per gigabytes when the available downlink EDAP resources areinadequate (for a scheduled downlink TBF in BTSs where EGPRS is enabled)because of PCU capacity. The formula may not give correct values if:
. the object aggregation level is smaller than the BSC level, and
. one or more BTSs in the area has more than one dynamic Abis poolconnected.
OSS4.0 is needed to collect all counters.
Formula (NetAct names):
Sum (DL_indadeq_time_minutes) /
Sum (DL GPRS payload_Gbyte + DL EGPRS payload_Gbyte)
=
sum (a.dl_mcs_limited_by_pcu) / (50 x 60)
------------------------------------------
sum over BTS with EGENA = Y
( b.rlc_data_blocks_dl_cs1 x 20
+ b.rlc_data_blocks_dl_cs2 x 30
+ sum over MCS-1 (xx) x 22
+ sum over MCS-2 (xx) x 28
+ sum over MCS-3 (xx) x 37
+ sum over MCS-4 (xx) x 44
+ sum over MCS-5 (xx) x 56
+ sum over MCS-6 (xx) x 74
+ sum over MCS-7 (xx/2) x 112
+ sum over MCS-8 (xx/2) x 136
+ sum over MCS-9 (xx/2) x 148
+ sum over MCS-11(xx) x 36
+ sum over MCS-12(xx) x 50
) / (1024 x 1024 x 1024)
where xx = (c.dl_rlc_blocks_in_ack_mode
+ c.dl_rlc_blocks_in_unack_mode)
Counters from table(s):
a = p_nbsc_dynamic_abis
b = p_nbsc_packet_control_unit
c = p_nbsc_coding_scheme
Unit:
min/GB
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4.4 Gb congestion KPIs
Downlink Gb load, S9 (frl_8a)
Use:
Indicates the load percentage of the frame relay bearer for incoming data from theSGSN.
Formula:
sum(8 x (dlci_1_bytes_rec
+ dlci_2_bytes_rec
+ dlci_3_bytes_rec
+ dlci_4_bytes_rec
+ dlci_5_bytes_rec)/(period_duration x 60))
100 x ------------------------------------------------ %
sum per frbc over all unlocked child nsvc
(c_nsvc.committed_info_rate x 16);
frbc object_instance = bearer_id in p_nbsc_frame_relay
Counters from table(s):
p_nbsc_frame_relay
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5 PDTCH quality KPIsDownlink GPRS RLC throughput, S10 (trf_235b)
Use:
Indicates the impact of the radio link quality on net data rate per used timeslot,taking into account the retransmissions and coding scheme selection. The lowerthe value, the poorer the radio link quality. This causes retransmissions and theuse of lower coding schemes.
The numerator does not contain the RLC header bytes; neither does the MACheader. This is because the aim is to count the data volume from as close to theuser’s point of view as possible.
Formula (NetAct names):
GPRS ACK DL payload data in (kilobits)
---------------------------------------- =
GPRS ACK DL time for data transfer (sec)
sum((a.rlc_data_blocks_dl_CS1
- a.rlc_data_blocks_dl_unack) x 20
+ a.rlc_data_blocks_dl_CS2 x 30
+ sum over MCS-11 (b.DL_RLC_BLOCKS_IN_ACK_MODE) x 36
+ sum over MCS-12 (b.DL_RLC_BLOCKS_IN_ACK_MODE) x 50) x 8 /1000
------------------------------------------------------------------
sum (a.rlc_data_blocks_dl_cs1
- a.rlc_data_blocks_dl_unack
+ a.rlc_data_blocks_dl_cs2
+ RETRA_RLC_DATA_BLOCKS_DL_CS1
+ RETRA_RLC_DATA_BLOCKS_DL_CS2
+ sum over MCS-11..12 (b.DL_RLC_BLOCKS_IN_ACK_MODE
+ b.RETRANS_RLC_DATA_BLOCKS_DL)) /50
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit:
kbit/sec/TSL
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Uplink GPRS RLC throughput, S11.5 (trf_233c)
Use:
Indicates the impact of the radio link quality on net data rate per used timeslot,taking into account the retransmissions and coding scheme selection. The lowerthe value, the poorer the radio link quality. This causes retransmissions and theuse of lower coding schemes.
The numerator does not contain the RLC header bytes; neither does the MACheader. This is because the aim is to count the data volume from as close to theuser’s point of view as possible.
The denominator is built on the fact that one timeslot can carry 50 RLC blocksper second.
Formula (NetAct names):
GPRS UL payload ACK data in (kilobits)
----------------------------------------- =
GPRS UL time for ACK data transfer (sec)
sum((a.rlc_data_blocks_ul_cs1
- a.rlc_data_blocks_ul_unack) x 20
+ a.rlc_data_blocks_ul_cs2 x 30
+ sum over MCS-11 (b.ul_rlc_blocks_in_ack_mode) x 36
+ sum over MCS-12 (b.ul_rlc_blocks_in_ack_mode) x 50) x 8 /1000
------------------------------------------------------------------
sum(a.rlc_data_blocks_ul_cs1
- a.rlc_data_blocks_ul_unack
+ a.rlc_data_blocks_ul_cs2
+ a.retra_data_blocks_ul_cs1
+ a.retra_data_blocks_ul_cs2
+ sum over MCS-11..12 (b.ul_rlc_blocks_in_ack_mode
+ b.retrans_rlc_data_blocks_ul)) /50
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit:
kbit/sec/TSL
Downlink EGPRS RLC throughput, S10 (trf_236)
Use:
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Indicates the impact of the radio link quality on net data rate per used timeslot,taking into account the retransmissions and coding scheme selection. The lowerthe value, the poorer the radio link quality. This causes retransmissions and theuse of lower coding schemes.
The numerator does not contain the RLC header bytes; neither does the MACheader. This is because the aim is to count the data volume from as close to theuser’s point of view as possible.
Formula:
EGPRS ACK DL payload data in (kilobits)
---------------------------------------- =
EGPRS ACK DL time for data transfer (sec)
(sum over MCS-1 (xx) x 22
+ sum over MCS-2 (xx) x 28
+ sum over MCS-3 (xx) x 37
+ sum over MCS-4 (xx) x 44
+ sum over MCS-5 (xx) x 56
+ sum over MCS-6 (xx) x 74
+ sum over MCS-7 (xx) x 56
+ sum over MCS-8 (xx) x 68
+ sum over MCS-9 (xx) x 74) x 8/1000
-------------------------------------
sum over msc1…6 of (yy)/50
+ sum over msc7…9 of (yy)/2/50
where
xx = b.dl_rlc_blocks_in_ack_mode
yy = b.dl_rlc_blocks_in_ack_mode
+ b.retrans_rlc_data_blocks_dl
Counters from table(s):
b = p_nbsc_coding_scheme
Unit:
kbit/sec/TSL
Average effective ACK EGPRS Uplink throughput per used TSL, S11.5(trf_234)
Use:
Indicates the impact of the radio link quality on net data rate per used timeslot,taking into account the retransmissions and coding scheme selection. The lowerthe value, the poorer the radio link quality. This causes retransmissions and theuse of lower coding schemes.
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The numerator does not contain the RLC header bytes; neither does the MACheader. This is because the aim is to count the data volume from as close to theuser’s point of view as possible.
The denominator is built on the fact that one timeslot can carry 50 RLC blocksper second.
Formula (NetAct names):
EGPRS UL payload ACK data in (kilobits)
--------------------------------------- =
EGPRS UL time for ACK data transfer (sec)
(sum over MCS-1 (xx)*22
+ sum over MCS-2 (xx)*28
+ sum over MCS-3 (xx)*37
+ sum over MCS-4 (xx)*44
+ sum over MCS-5 (xx)*56
+ sum over MCS-6 (xx)*74
+ sum over MCS-7 (xx)*56
+ sum over MCS-8 (xx)*68
+ sum over MCS-9 (xx)*74)*8/1000
---------------------------------------
sum over MCS1..6 of (yy)/50
+ sum over MCS7..9 of (yy)/2 /50
where
xx = b.ul_rlc_blocks_in_ack_mode
yy = b.ul_rlc_blocks_in_ack_mode
+ b.retrans_rlc_data_blocks_ul
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit:
kbit/sec/TSL
TBF establishment failure ratio, S12 (tbf_66)
Use:
This KPI calculates ratio of failed UL and DL TBFs due to no response from MSto all TBFs (UL and DL).
Formula (NetAct names):
sum(DL_TBF_Establishment_Failed + DL_EGPRS_TBF_REL_DUE_NO_RESP)
+ sum(UL_TBF_Establishment_Failed + UL_EGPRS_TBF_REL_DUE_NO_RESP)
100 * -----------------------------------------------------------
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sum(Nbr_Of_DL_TBF + Nbr_Of_UL_TBF)
Unit:
%
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6 Mobility KPIsDownlink flush per minute, S9 (tbf_64)
Use:
Indicates the number of temporary block flows (TBFs) that are interrupted by cellreselections per "TBF minute". Indicates the level of subscriber mobility.
Formula (NetAct names):
60 x 100 x DL_TBF_REL_DUE_TO_FLUSH/AVE_DUR_DL_TBF_SUM
Counters from table(s):
p_nbsc_packet_control_unit
Unit:
number/min
NCCR success ratio, S12 (nccr_13)
Use:
Ratio of successful NCCRs to total NCCR attempts.
Formula (NetAct names):
nccr_succ_flush_received
100 * ----------------------------
nccr_1
Unit:
%
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7 Availability KPIsData service availability ratio, S9 (ava_68)
Use:
Data service availability (DSA) gives the estimated percentage of on-air GPRS-capable BTSs that are able to provide the GPRS service. Detects outages in theGPRS and EGPRS services. Outages may be caused by a fault in hardware orsoftware.
Note that in some situations the system can generate an 11-bit random accesschannel (RACH) burst without a real mobile station (MS) on the cell. This causestemporary block flow (TBF) establishments in the BSC and also increments thepacket_ch_req counter. Therefore, the limit used in the condition "packet_ch_req>= 100" should be adjusted according to the real network conditions. Often, thevalue of 100 is enough in many cases and should be used as the default setting.This KPI should be used with a 24-hour measurement period. However,excluding maintenance hours at night from the data collection time might help toreduce false triggering.
Formula (logical):
100 x ((1 - Subscriber access outage rate)
x (1 - Number of no data activity case))
Formula (NetAct names):
100 x
(
1 - (
ava_71
--------------------------------
count(x)
where (a.packet_ch_req >= 100)
)
x
1 - (
ava_72
---------------------------------------------------------------
count(x)
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Availability KPIs
where ((b.ave_tch_busy_full + b.ave_tch_busy_half) >= 0.2) and
(b.ave_gprs_channels_sum > 0) and
(c.tch_call_req > 10)
)
)
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_res_avail
c = p_nbsc_service
Unit:
%
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8 User experience KPIsLLC throughput for 4-tsl EDGE MSs, S12 (llc_3a)
Use:
Indicates, on average, successfully transferred kilobits per second when at leastone of the following conditions is met:
. temporary block flow (TBF) duration is longer than four seconds
. logical link control (LLC) bytes are more than 1560
Formula (NetAct names):
sum(VWTHR_NUMERATOR_EDGE_4_DL) * 8
-------------------------------------
sum(VWTHR_DENOMINATOR_EDGE_4_DL) * 10
Counters from table(s):
p_nbsc_packet_control_unit
Unit:
kbps
LLC throughput for GPRS MSs (for each QoS class), S12 (llc_4a)
Use:
Indicates, on average, successfully transferred kilobits per second when at leastone of the following conditions is met:
. temporary block flow (TBF) duration is longer than four seconds
. logical link control (LLC) bytes are more than 1560
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Note
Names used from OSS4 CDSet2 ongoing.
Formula (NetAct names):
sum(VWTHR_NUMERATOR_GPRS) * 8
-------------------------------
sum(VWTHR_DENOMINATOR_GPRS) * 10
Counters from table(s):
p_nbsc_QoS
Unit:
kbps
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9 Reference for used formulas
The KPIs described here have been used in the previous benchmark KPIdefinitions.
Average CS traffic, S12 (trf_171a)
Use:
This is a speech (circuit switched) traffic indicator. Speech traffic is a basicindicator needed to see how much TCH capacity is consumed. When the trafficincreases without the increase in capacity, the probability of blocking increases.The relationship between traffic, capacity and blocking is described for speechtraffic in the formula known as Erlang B. This KPI includes all types of CS traffic(single TCH, HSCSD, DTM).
Formula (NetAct names):
trf_202a ; CS traffic on normal TRXs
+ trf_170 ; CS traffic on extended TRXs
Unit
E
Average CS traffic, extended TRXs, S12 (trf_170)
Use:
This is a speech (circuit switched) traffic indicator. Speech traffic is a basicindicator needed to see how much TCH capacity is consumed. When the trafficincreases without the increase of the capacity, the probability of blocking grows.The relationship between traffic, capacity and blocking is described for speechtraffic in the formula known as Erlang B. This KPI includes all types of CS traffic(single TCH, HSCSD) on extended TRXs.
Formula (NetAct names):
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Reference for used formulas
sum(decode(trx_type,1,ave_busy_tch))
-----------------------------------
avg(decode(trx_type,1,res_av_denom14)) * count(distinct period_start_time)
Counters from table(s):
p_nbsc_res_avail
Unit
E
Average CS traffic, normal TRXs, S12 (trf_202a)
Use:
This is a speech (circuit switched) traffic indicator. Speech traffic is a basicindicator needed to see how much TCH capacity is consumed. When the trafficincreases without the increase in capacity, the probability of blocking grows. Therelationship between traffic, capacity and blocking is described for speech trafficin the formula known as Erlang B. This KPI includes all types of CS traffic(single TCH, HSCSD, DTM) on normal TRXs.
Formula (NetAct names):
tcount(distinct period_start_time) *
(
sum(decode(trx_type,0,a.ave_busy_tch))
-------------------------------------
avg(decode(trx_type,0,a.res_av_denom14))
+
sum(decode(trx_type,0,((0.5*b.DTM_duration_sum_HR
+ b.DTM_duration_sum_FR) /100)))
-------------------------------------------------
avg(decode(trx_type,0,(period_duration*60)))
)
Counters from table(s):
a = p_nbsc_res_avail
b = p_nbsc_ps_dtm
Unit
E
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DL DTM PS payload, S12 (dtm_5)
Use:
DL payload (GPRS plus EDGE) is generated by DTM PS connections.
Formula (NetAct names):
(sum(a.DL_RLC_CS1_BLKS_TO_DTM_MS*20 + a.DL_RLC_CS2_BLKS_TO_DTM_MS*30) +
sum over MCS-1 (xx*22) +
sum over MCS-2 (xx*28) +
sum over MCS-3 (xx*37) +
sum over MCS-4 (xx*44) +
sum over MCS-5 (xx*56) +
sum over MCS-6 (xx*74) +
sum over MCS-7 (xx/2) * 112 +
sum over MCS-8 (xx/2) * 136 +
sum over MCS-9 (xx/2) * 148 +
sum over MCS-11 (xx*36) +
sum over MCS-12 (xx*50))/1024
where xx = (b.DL_RLC_MCS_N_BLKS_TO_DTM_MS)
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit
kbyte
Ratio of served GPRS DL TSL requests, S9 (msl_6)
Use:
Indicates the ratio of timeslot allocations to requests in downlink.
Formula:
sum(alloc_1_TSL_DL + 2 x alloc_2_TSL_DL
+ 3 x alloc_3_TSL_DL
+ 4 x alloc_4_TSL_DL)
100 x -------------------------------------------------------------------- %
sum(req_1_TSL_DL + 2 x req_2_TSL_DL + 3 x req_3_TSL_DL + 4 x req_4_TSL_DL)
Counters from table(s):
p_nbsc_packet_control_unit
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Reference for used formulas
Total NCCR attempts, S11.5 (nccr_1)
Use:
Total NCCR attempts include an attempt when any of the NCCR triggers isfulfilled.
Formula (NetAct names):
sum(
a.NCCR_NOT_STARTED_DUE_AC
+ b.NCCR_QC_TRIG_NO_GOOD_NEIG
+ b.NCCR_SERV_ISNCCR_NO_GOOD_NEIG
+ a.PCCO_TO_GPRS_MS_DUE_PWR_BDGT
+ a.PCCO_TO_EGPRS_MS_DUE_PWR_BDGT
+ a.PCCO_SENT_DUE_SERV_ISNCCR
+ a.PCCO_SENT_DUE_COVERAGE_ISNCCR
+ a.PCCO_SENT_DUE_QUAL_CTRL
)
Counters from table(s):
a = P_NBSC_CELL_RESELECTION
b = P_NBSC_PACKET_CONTROL_UNIT
Unit
#
UL DTM PS payload, S12 (dtm_4)
Use:
UL payload (GPRS plus EDGE) generated by DTM PS connections.
Formula (NetAct names):
(sum(a.UL_RLC_CS1_BLKS_FROM_DTM_MS*20 + a.UL_RLC_CS2_BLKS_FROM_DTM_MS*30) +
sum over MCS-1 (xx*22) +
sum over MCS-2 (xx*28) +
sum over MCS-3 (xx*37) +
sum over MCS-4 (xx*44) +
sum over MCS-5 (xx*56) +
sum over MCS-6 (xx*74) +
sum over MCS-7 (xx/2) * 112 +
sum over MCS-8 (xx/2) * 136 +
sum over MCS-9 (xx/2) * 148 +
sum over MCS-11 (xx*36) +
sum over MCS-12 (xx*50))/1024
where xx = (b.UL_RLC_MCS_N_BLKS_FROM_DTM_MS)
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Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit
kbyte
Uplink GPRS RLC blocks, S10 (trf_203b)
Formula (NetAct names):
Actual UL data blocks
Sum (a.rlc_data_blocks_ul_cs1 + a.rlc_data_blocks_ul_cs2
+ sum over MCS-11 (b.ul_rlc_blocks_in_ack_mode
+ b.ul_rlc_blocks_in_unack_mode)
+ sum over MCS-12 (b.ul_rlc_blocks_in_ack_mode
+ b.ul_rlc_blocks_in_unack_mode))
Counters from table(s):
a = p_nbsc_packet_control_unit
b = p_nbsc_coding_scheme
Unit
Number of blocks
Uplink EGPRS RLC blocks, S10 (trf_204)
Formula (NetAct names):
Actual UL data blocks
sum over MCS1-9 of
(ul_rlc_blocks_in_ack_mode + ul_rlc_blocks_in_unack_mode)
Counters from table(s):
p_nbsc_coding_scheme
Unit
Number of blocks
Subscriber access outage rate, S9 (ava_71)
Use:
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Reference for used formulas
Subscriber access outage rate is triggered when a significant number of packet-switched service attempts are made on the BTS, but none of the attempts aresuccessful. Note that when Subscriber access outage rate is triggered, it indicatesa hardware or software fault that causes GPRS/EGPRS service outage.
Formula (NetAct names):
count(x)
where (packet_ch_req > 100) and
(nbr_of_ul_tbf + no_radio_res_ava_ul_tbf) > 80 and
(ave_dur_ul_tbf_sum = 0 or ave_dur_dl_tbf_sum=0))
Counters from table(s):
p_nbsc_packet_control_unit
Unit
Number of attempts
Number of no data activity cases, S9 (ava_72)
Use:
Number of no data activity cases is triggered when a fair amount of traffic issetting up on a GPRS-capable BTS but no packet-switched service attempts arebeing made. If there are no dedicated GPRS radio timeslots (RTLSs), Number ofno data activity cases might be pegged if the peak number of circuit-switchedRTSLs equals the maximum number of traffic channels and GPRS RTSLs duringall packet-switched connection attempts within the measurement period.
Note that the triggering of Number of no data activity cases indicates a problemwith the SYSTEM INFORMATION TYPE 13 message where mobile stations ignorethe BTS/SEG for packet-switched connections.
Formula (NetAct names):
count(x)
where (a.ave_tch_busy_full + a.ave_tch_busy_half) >= 0.2 and
(a.ave_gprs_channels_sum > 0) and
(b.packet_ch_req = 0 and c.tch_call_req > 10)
Counters from table(s):
a = p_nbsc_res_avail
b = p_nbsc_packet_control_unit
c = p_nbsc_service
Unit
Number of cases
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10 Traffic monitoring principles
Once the network has been dimensioned, the network planning, implementation,and optimisation phases follow. Network planning typically includes a detailedconfiguration and parameter plan, where features are planned in detail. Networkmonitoring is a part of a typical optimisation process. It can be used to veritywhether the original dimensioning assumptions were correct. Traffic monitoringis used to trigger a network configuration change when the amount of traffic ishigher or lower than assumed in the original dimensioning.
To perform monitoring, we can use the values of the counters implemented in thenetwork element or some formulas involving several of these counters. Ingeneral, performance indicators (PIs) and key performance indicators (KPIs) aredefined.
A KPI is a value that presents some vital information about the network. TheKPIs are mapped directly from PIs, a formula of several PIs, or directly fromnetwork counters.
Measurements
In Nokia BSS, the BSC is responsible for traffic measurements. Eachmeasurement type can activate a certain amount of counters, and eachmeasurement has to be activated for all required BSCs. Typically, measurementsprovide data for all BTSs under the BSC. In addition to measurements,observations can be used for data collection. Observations are specialmeasurements for a limited number of network objects. Observations typicallyprovide a large amount of data. Measurements and observations are divided intothe following groups according to their function:
. Call control measurements (CSW)
. GPRS measurements (PSW)
. Transmission measurements
. Observations
The following are EGPRS measurements:
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. 72 Packet control unit measurement
. 73 RLC blocks per TRX measurement
. 74 Frame relay measurement
. 76 Dynamic Abis measurement
. 79 Coding scheme measurement
. 90 Quality of Service measurement
. 91 PBCCH availability measurement
. 95 GPRS cell reselection measurement
. 96 GPRS RX level and quality measurement
. 97 Enhanced Quality of Service measurement
. 98 Gb over IP measurement
Some of the above-mentioned measurements are related to optional features andare not useful if the feature has not been activated.
When BTS/BSC expansion needs are evaluated, monitoring both CSW and PSWtraffic is required. There are several CSW related measurements, but mostimportant for EGPRS are the following:
1. Traffic measurement
2. Resource availability measurement
3. Resource access measurement
4. Handover measurement
KPIs
The operator needs KPIs to monitor the performance of the network, totroubleshoot failures, and to ensure that the end user has the best possibleperception of the service. To improve the performance of the network it istherefore important to check how the network is performing. This can be done bylooking into different key performance indicators and setting the criteria for thenetwork improvement or deciding when to increase capacity.
EDGE KPIs are also available in the NetAct Reporter tool.
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Related topics
. BTS EDGE dimensioning
. Abis EDGE dimensioning
. BSC EDGE dimensioning
. Gb EDGE dimensioning
. SGSN EDGE dimensioning
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