Flex Abis(GBSS15.0 01)

GSM BSSGBSS15.0

Flex Abis Feature ParameterDescription

Issue 01

Date 2013-05-06

HUAWEI TECHNOLOGIES CO., LTD.

Copyright © Huawei Technologies Co., Ltd. 2013. All rights reserved.No part of this document may be reproduced or transmitted in any form or by any means without prior writtenconsent of Huawei Technologies Co., Ltd. Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.All other trademarks and trade names mentioned in this document are the property of their respective holders. NoticeThe purchased products, services and features are stipulated by the contract made between Huawei and thecustomer. All or part of the products, services and features described in this document may not be within thepurchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information,and recommendations in this document are provided "AS IS" without warranties, guarantees or representationsof any kind, either express or implied.

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Email: [email protected]

Issue 01 (2013-05-06) Huawei Proprietary and ConfidentialCopyright © Huawei Technologies Co., Ltd.

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mailto:[email protected]

Contents

1 About This Document..................................................................................................................11.1 Scope..............................................................................................................................................................................11.2 Intended Audience..........................................................................................................................................................11.3 Change History...............................................................................................................................................................1

2 Overview.........................................................................................................................................32.1 Introduction....................................................................................................................................................................32.2 Feature Support by NE...................................................................................................................................................3

3 Technical Description...................................................................................................................43.1 Working Principles.........................................................................................................................................................43.2 Networking Topology.....................................................................................................................................................63.3 Abis Transmission Link Establishment..........................................................................................................................63.4 Algorithm for TCHH Allocation Triggered by Abis Overload......................................................................................73.4.1 Abis Timeslot Allocation for TCH..............................................................................................................................83.4.2 Abis Timeslot Allocation for PDCH...........................................................................................................................9

4 Related Features...........................................................................................................................10

5 Impact on the Network...............................................................................................................115.1 Impact on System Capacity..........................................................................................................................................115.2 Impact on Network Performance..................................................................................................................................11

6 Engineering Guidelines.............................................................................................................126.1 When to Use Flex Abis.................................................................................................................................................126.2 Information to Be Collected.........................................................................................................................................126.3 Network Planning.........................................................................................................................................................126.4 Deployment Procedure.................................................................................................................................................126.4.1 Deployment Requirements........................................................................................................................................136.4.2 Data Preparation........................................................................................................................................................156.4.3 Feature Activation.....................................................................................................................................................236.4.4 Activation Observation..............................................................................................................................................256.4.5 Deactivation...............................................................................................................................................................256.5 Performance Optimization............................................................................................................................................266.6 Troubleshooting............................................................................................................................................................26

7 Parameters.....................................................................................................................................27

GSM BSSFlex Abis Feature Parameter Description Contents


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8 Counters........................................................................................................................................67

9 Glossary.........................................................................................................................................75

10 Reference Documents...............................................................................................................76

GSM BSSFlex Abis Feature Parameter Description Contents


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1 About This Document

1.1 ScopeThis document describes the GBFD-117301 Flex Abis feature, including its technicaldescription, feature dependencies, network impact, and engineering guidelines.

1.2 Intended AudienceThis document is intended for:

l Personnel who need to understand the Flex Abis featurel Personnel who work with Huawei GSM products

1.3 Change HistoryThis section provides information about the changes in different document versions.

There are two types of changes, which are defined as follows:

l Feature change: refers to a change in the Flex Abis feature of a specific product version.l Editorial change: refers to a change in wording or the addition of information that was not

described in the earlier version.

Document Issues

The document issues are as follows:l 01 (2013-05-06)l Draft A (2013-02-27)

01 (2013-05-06)

This is the first commercial release of GBSS15.0.

Compared with Draft A (2013-02-27), Issue 01 (2013-05-06) has no change.

GSM BSSFlex Abis Feature Parameter Description 1 About This Document


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Draft A (2013-02-27)This is a draft.

Compared with Issue 01 (2012-04-28) of GBSS14.0, Draft A (2013-02-27) of GBSS15.0incorporates the changes described in the following table.

Change Type Change Description Parameter Change

Feature change Added section "4 RelatedFeatures."

None

Editorial change None None

GSM BSSFlex Abis Feature Parameter Description 1 About This Document


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2 Overview

2.1 IntroductionThe traffic of packet switched (PS) services and circuit switched (CS) services in cells and BTSsis not constantly heavy. In most cases, if a BTS is overloaded, the load of other BTSs is light.Similarly, if the PS traffic is heavy, the CS traffic is light.

Flex Abis is a mode of allocating the Abis transmission resources. With the Flex Abis feature,Abis transmission resources form a resource pool. The resources in the resource pool can beshared by CS and PS services in different cells and BTSs.

Abis transmission resources can be used more effectively if Flex Abis is used in the followingscenarios:

l Large-capacity BTSs with multiple cellsl Cascaded BTSsl EGPRS-capable cells

2.2 Feature Support by NE

Table 2-1 Feature support by NE

Feature Name BSC6900 BSC6910 GBTS eGBTS

Flex Abis √ √ √ ×

NOTE

√ indicates that the NE supports this feature. × indicates that the NE does not support this feature.

GSM BSSFlex Abis Feature Parameter Description 2 Overview


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3 Technical Description

3.1 Working PrinciplesAbis transmission resources are allocated in either fixed or dynamic mode.

l Fixed allocation modeIn fixed allocation mode, Um-interface channels including traffic channels (TCHs) andstatic packet data channels (PDCHs) are always mapped to Abis timeslots. The Abistimeslots are occupied even when the Um-interface channels are idle.

l Dynamic allocation modeIn dynamic allocation mode, Abis timeslots form a resource pool. The Abis timeslots areallocated to Um-interface channels only when the channels are occupied. As a result, theUm-interface channel resources can be much more abundant than the Abis transmissionresources, and the Abis transmission resources can be fully used in different time slices,improving the resource usage, as shown in Figure 3-1.

GSM BSSFlex Abis Feature Parameter Description 3 Technical Description


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Figure 3-1 Flex Abis working principles

Flex Abis timeslots in a resource pool do not include the Abis timeslots occupied by staticPDCHs, semipermanent connection timeslots, monitoring timeslots, signaling link timeslots, orAbis timeslots or idle timeslots in fixed allocation mode.

Flex Abis timeslots in a resource pool are allocated to TCHs and PDCHs.

l Full-rate TCHs (TCHFs) and half-rate TCHs (TCHHs) are allocated 16 kbit/s and 8 kbit/stimeslots, respectively.

l PDCHs are allocated 16 kbit/s timeslots.

For details about channel allocation, see Channel Management Feature ParameterDescription and GPRS/EGPRS Channel Management Feature Parameter Description. IfAbis timeslots are insufficient, CS services preempt timeslots occupied by PS services.

Flex Abis is recommended in the following scenarios to improve the resource usage:

l The traffic volumes of multi-level cascaded or large-capacity BTSs or the cells under thesetypes of BTSs do not reach their peak values at the same time.

l PS services account for a large proportion of the services in a cell.l Transmission resources are insufficient and the rent of transmission equipment is high. For

example, satellite transmission.



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3.2 Networking TopologyThe BSC supports the networking topology with multi-level Flex Abis resource pools shared bycascaded BTSs, as shown in Figure 3-2.

Figure 3-2 Flex Abis networking topology

Abis transmission is implemented by satellite or using one or more E1/T1 cables.

Resources on Abis transmission links form resource pools and are shared by CS and PS services.

l Link 1 indicates Abis transmission links between the BSC and BTS 0. Transmissionresources on Link 1 form Pool 0. Resources in Pool 0 can be shared by CS and PS servicesprocessed by BTS 0, BTS 1, and BTS 2.

l Link 2 indicates Abis transmission links between BTS 0 and BTS 1. Transmission resourceson Link 2 form Pool 1. Resources in Pool 1 can be shared by CS and PS services processedby BTS 1 and BTS 2.

l Link 3 indicates Abis transmission links between BTS 1 and BTS 2. Transmission resourceson Link 3 form Pool 2. Resources in Pool 2 can be shared by CS and PS services processedby BTS 2.

3.3 Abis Transmission Link EstablishmentWhen Flex Abis is enabled, the BSC must allocate Abis timeslots and establish transmissionlinks between the BSC and BTSs.



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Figure 3-3 Process of establishing Abis transmission links

As shown in Figure 3-3, when allocating a channel to an MS in BTS 2, the BSC mustdynamically allocate the Abis timeslots on Link 1, Link 2, and Link 3 to the channel, and theninstruct BTS 0, BTS 1, and BTS 2 to establish transmission links for the channel. A dedicatedextended signaling link (ESL) to carry signaling must be configured for each Flex Abis-capableBTS.

In 64 kbit/s multiplexing mode, ESLs and operation and maintenance links (OMLs) must bephysically multiplexed on the same 64 kbit/s E1 timeslot. To increase the number of ESLs, youmust reduce the number of radio signaling links (RSLs). You can change the maximum numberof RSLs multiplexed with OMLs by changing MPMODE(BSC6900,BSC6910).

The rules for setting MPMODE(BSC6900,BSC6910) are as follows:

l In most cases, set MPMODE(BSC6900,BSC6910) to MODE2_1. If this parameter is setto a large value, the RSLs will become congested. Therefore, set this parameter toMODE5_1 or MODE6_1 only when the traffic on a BTS is light.

l During the initial configuration of a BTS, set FLEXABISMODE(BSC6900,BSC6910) toFLEX_ABIS or SEMI_ABIS to enable Flex Abis.

l After the BTS configuration is complete, set FLEXABISMODE(BSC6900,BSC6910) toFLEX_ABIS or SEMI_ABIS to enable Flex Abis, if required.

3.4 Algorithm for TCHH Allocation Triggered by AbisOverload



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3.4.1 Abis Timeslot Allocation for TCHThe BSC allocates Abis timeslots in a Flex Abis resource pool to a TCH according to the TCHtype.

l For a TCH/F, 16 kbit/s Abis timeslots are allocated.l For a TCH/H, 8 kbit/s Abis timeslots are allocated.

After Flex Abis is enabled, the BSC generally allocates TCH/Fs. If the Abis interface experienceinsufficient transmission resources prior to the Um interface, the BSC triggers TCH/H allocationbased on the load of Abis transmission resources, increasing the access success rate.

Table 3-1 Flex Abis timeslot allocation for TCHs

If... Then...

IDLE_BAND/ALL_BAND< TDMCONGTH(BSC6900,BSC6910)

Preferentially allocatingTCH/Hs to new CS servicesis triggered.

The BSC preferentiallyallocates TCH/Hs to new CSservices. This decreases theFlex Abis timeslots occupiedby a new CS service.

Converting TCH/Fs to TCH/Hs for CS services istriggered.

The BSC hands over MSsthat occupy TCH/Fs to TCH/Hs. This decreases the FlexAbis timeslots occupied byongoing services, therebyallowing more users to accessthe network with limited FlexAbis timeslots and improvingthe Abis transmissionresource usage.

IDLE_BAND/ALL_BAND ≥ TDMCONGCLRTH(BSC6900,BSC6910)

The BSC stops preferentiallyallocating TCH/Hs to newCS services and convertingTCH/Fs to TCH/Hs for CSservices.

NOTE

IDLE_BAND represents the bandwidth of the idle Flex Abis timeslots in the resource pool.

ALL_BAND represents the bandwidth of all Flex Abis timeslots in the resource pool.



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NOTE

A congestion threshold is set to control the transmission bandwidth usage. If the threshold is reached, thefollowing load control methods are used:

l Decreasing the PS service rate

l Allocating TCHHs to MSs requesting CS services

l Handing over MSs performing CS services from TCHFs to TCHHs

The priorities of these load control methods are specified by the parameters LDRFST(BSC6900,BSC6910), LDRSND(BSC6900,BSC6910), and LSRTRD(BSC6900,BSC6910). When theFlex Abis feature is enabled, you are not advised to use the load control method of limiting the AMR ratefor MSs requesting CS services.

3.4.2 Abis Timeslot Allocation for PDCHThe BSC allocates Abis timeslots in a Flex Abis resource pool to PDCHs as follows:

l The BSC allocates 16 kbit/s sub-timeslots to the primary link.l The BSC dynamically allocates sub-timeslots to secondary links at a step of 16 kbit/s based

on the coding rate required by the Um interface.

NOTE

When Flex Abis is enabled, the BSC can dynamically allocate Abis timeslots without configuring any staticPDTCHs or setting TSCOUNT(BSC6900,BSC6910) if the actual traffic volume is far lower than theestimated traffic volume in the network plan. That is, the BSC dynamically allocates both the primary andsecondary links to PS services.

If the PS traffic volume remains low, you do not need to configure static PDTCHs or setTSCOUNT(BSC6900,BSC6910). When the CS traffic is heavy, CS services may preempt allAbis timeslots. As a result, there are no available Abis timeslots for subsequent PS services.

If the CS traffic is heavy, you need to reserve some static PDTCHs and set TSCOUNT(BSC6900,BSC6910) to reserve dedicated timeslots for PS services. This ensures that the BSCcan process GPRS or EGPRS services properly.



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4 Related Features

Table 4-1 Related Features

Feature PrerequisiteFeature

MutuallyExclusive Feature

Affected Feature

Flex Abis None l GBFD-11670116Kbit RSL andOML on A-bisInterface

l GBFD-118601Abis over IP

l GBFD-118611Abis IP over E1/T1

l GBFD-118401AbisTransmissionOptimization

l GBFD-117801Ring Topology

l GBFD-116601Abis Bypass

NOTEGBFD-117801 RingTopology can be usedwith ring topology I,but this feature andring topology II aremutually exclusive.

None

GSM BSSFlex Abis Feature Parameter Description 4 Related Features


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5 Impact on the Network

5.1 Impact on System CapacityThe Flex Abis feature allows cells under large-capacity BTSs, multi-level cascaded BTSs andEDGE-capable cells to share Abis transmission resources.

In most cases, the traffic volumes of different BTSs, different cells under the same BTS, and CSand PS services do not reach their peak values at the same time. When transmission resourcesare available, Flex Abis enables cells to support more carriers than the fixed Abis feature,increasing system capacity.

5.2 Impact on Network PerformanceIf the load control method of decreasing the PS service rate is used, the settings of the followingparameters may affect network performance:

l RelFlexAbisForLdr(BSC6900,BSC6910)– If this parameter is set to ON(On), the BSC releases secondary links on a PDCH in real

time. As a result, the transmission bandwidth reduces, decreasing the proportion of high-rate coding schemes and PS throughput. The bandwidth used by CS services increases,decreasing the proportion of TCHHs.

– If this parameter is set to OFF(Off), the bandwidth used by PS services remainsunchanged, increasing the proportions of high-rate coding schemes and TCHHs as wellas increasing PS throughput.

l UlCsAdjForAbisRel(BSC6900,BSC6910)– If this parameter is set to ON(On), the BSC adjusts uplink coding schemes in real time

when the bandwidth for PS services is insufficient. This decreases the call drop rate andthe proportion of high-rate coding schemes.

– If this parameter is set to OFF(Off), the BSC does not adjust uplink high-rate codingschemes even if the bandwidth for PS service is insufficient. This increases the call droprate but the proportion of high-rate coding schemes remains unchanged.

GSM BSSFlex Abis Feature Parameter Description 5 Impact on the Network


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6 Engineering Guidelines

6.1 When to Use Flex AbisIt is recommended that this feature be used in the following scenarios:

l The traffic volumes of multi-level cascaded or large-capacity BTSs or the cells under thesetypes of BTSs do not reach their peak values at the same time.

l PS services account for a large proportion of the services in a cell.l Transmission resources are insufficient and the rent of transmission equipment is high. For

example, satellite transmission.

6.2 Information to Be CollectedNone

6.3 Network PlanningWhen Flex Abis is enabled, Digital Cross Connect (DXX) devices need to be supported. Thelimitations in using this feature are as follows:

l DXX cascading network does not support Flex Abis.l In ring topology I network, DXX does not support Flex Abis.l If faults occur during DXX timeslot switching, no audio will occur.

6.4 Deployment Procedure

GSM BSSFlex Abis Feature Parameter Description 6 Engineering Guidelines


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6.4.1 Deployment Requirements

Table 6-1 Deployment requirements

Aspect Requirement

Related features See chapter "4 Related Features."

BSC None

BTS The BTS3900B and BTS3X series cannot beused because they do not support this feature.The details are as follows:l If a BTS3900B or 3X series base station

functions as a root node in the chain or treetopology, none of the base stations in thechain or tree support Flex Abis.

l If a BTS3900B or 3X series base stationfunctions as a lower-level base station ofBTSs that support Flex Abis, Flex Abiscan be enabled on an upper-level BTSonly when both the following conditionsare met:Flex Abis Mode for the base station is setto SEMI_ABIS(Semisolid Abis).FlexAbis Mode for the upper-level BTS is setto FLEX_ABIS(Flex Abis).

GSM networking The Abis interface uses TDM transmission.

MS None

MSC None

License The license controlling this feature has beenactivated. For details on how to activate thelicense, see License Management FeatureParameter Description. For details aboutlicense items, see License Control ItemDescription.



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Aspect Requirement

Others A GSM BTS and its cells have beenconfigured.If a ring topology needs to be configured, onlyBTS ring topology I is supported. To deployboth BTS ring topology I and Flex Abis, doas follows:l Configure Flex Abis on all BTSs, and

configure only one E1 cable each for theclockwise and counter-clockwisedirections in the ring.

l Do not use the Abis Bypass feature on anyBTS.

l Do not configure 16 kbit/s link accessprocedure on the D channel (LAPD)signaling links for any BTS.

l Do not use the Abis timeslot self-detectionand self-healing function on any BTS.



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6.4.2 Data Preparation

Table 6-2 Data preparation

ParameterName

Parameter ID NE Remarks Data Source

Flex Abis Mode FLEXABISMODE(BSC6900,BSC6910)

BSC6900/BSC6910

l PrinciplesforconfiguringcascadedBTSsTo enableFlex Abis fora cascadedBTS, setFlex AbisMode toFLEX_ABIS(Flex Abis)for its upper-level BTSs.If Flex AbisMode is settoSEMI_ABIS(SemisolidAbis) for acascadedBTS, setFlex AbisMode toSEMI_ABIS(SemisolidAbis) for allits lower-level BTSs.Use the E1port of theprimarycabinetgroup toconnect theprimarycabinetgroup of thelevel-1 BTSto a BSCinterfaceboard. Usethe internal

Networkplanning



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ParameterName


connectionsof theprimarycabinetgroup or theE1 port ofthesecondarycabinetgroup toconnect thesecondarycabinetgroup to aBSCinterfaceboard.Use only theE1 ports ofthe primarycabinetgroups tointerconnectcascadedBTSs. Usethe internalconnectionsof theprimarycabinetgroup of alower-levelBTS toconnect thesecondarycabinetgroup of theBTS to anupper-levelBTS, andthen to aBSCinterfaceboard.Alternatively, use the E1port of thesecondarycabinet



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ParameterName


group todirectlyconnect theBTS to aBSCinterfaceboard. Notethatsecondarycabinetgroupsbelonging tothe sameBTS cannotbe cascaded.One BTScan onlyconnect toone upper-level BTS.

l Principlesforconfiguringother BTSsRun the SETBTSFORBIDTScommand toforbidtimeslots,excepttimeslots infixedallocationmode, suchas signalingtimeslotsandmonitoringtimeslots onE1 links for aBTS enabledwith FlexAbis. Forbidspecifiedtimeslotswhen onlysome



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ParameterName


timeslots onan E1 portcan be usedor in certainscenarios,such assatellitetransmission.

MultiplexingMode

MPMODE(BSC6900,BSC6910)

BSC6900/BSC6910

If this parameteris set to a largevalue, the radiosignaling links(RSLs) willbecomecongested.Therefore, setthis parameter toMODE5_1 orMODE6_1only when thetraffic on a BTSis light.

Networkplanning

ReservedTrafficTimeslots on anE1/T1

RSVTCHTSNUM(BSC6900,BSC6910)

BSC6900/BSC6910

This parameterspecifies thenumber of 64kbit/s timeslotsfor TCH,dynamic PDCH,or secondarylinks on an E1/T1. Thesetimeslotsexclude thetimeslots forOML, ESL,RSL, and staticPDCH, fixedly-configured idletimeslots,monitoringtimeslots, andtransparenttimeslots.

Networkplanning



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ParameterName


TransmissionResourcePreemptingSupport

ENPREEMPTTRANSADMT(BSC6900,BSC6910)

BSC6900/BSC6910

To enable CSservices topreempt theAbis timeslotsoccupied by PSservices andallow high-priority MSs topreempt theAbis timeslotsoccupied bylow-priorityMSs when allAbis timeslotsare occupied, setthis parameter toON(On).This parameteris a BSC-levelparameter.Therefore, thesetting of thisparameter takeseffect on allBTSs under theBSC.

Networkplanning

Transport Type TRANST(BSC6900,BSC6910)

BSC6900/BSC6910

Set thisparameter toTDM(TDM).

Networkplanning

Congestionremain ratio

TDMCONGTH(BSC6900,BSC6910)

BSC6900/BSC6910

Set thisparameter to avalue less thanthat ofCongestionremain ratio toprevent ping-pong handoverswhentransmissionlinks arecongested.

Networkplanning



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ParameterName


Congestionclear remainratio

TDMCONGCLRTH(BSC6900,BSC6910)

BSC6900/BSC6910

Set thisparameter to avalue greaterthan that ofCongestionclear remainratio to preventping-ponghandovers whentransmissionlinks arecongested.

Networkplanning

TRM LoadThresholdswitch

LOADTHSW(BSC6900,BSC6910)

BSC6900/BSC6910

If this parameteris set to ON(On), loadcontrol isenabled whentransmissionlinks arecongested. Ifthis occurs, setTRM loadthresholdindex to specifythe thresholdused for loadcontrol.

Networkplanning

TRM loadthreshold index

TRMLOADTHINDEX(BSC6900,BSC6910)

BSC6900/BSC6910

The value of thisparameter mustbe unique.

Networkplanning

LDR First LDRFST(BSC6900,BSC6910)

BSC6900/BSC6910

If this parameteris set to a valueother thanCLOSE, ensurethat the value isdifferent fromthe value ofLDR Second,LDR Third, orLDR Fourth.

Networkplanning



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ParameterName


LDR Second LDRSND(BSC6900,BSC6910)

BSC6900/BSC6910

If this parameteris set to a valueother thanCLOSE, ensurethat the value isdifferent fromthe value ofLDR First,LDR Third, orLDR Fourth.

Networkplanning

LDR Third LSRTRD(BSC6900,BSC6910)

BSC6900/BSC6910

If this parameteris set to a valueother thanCLOSE, ensurethat the value isdifferent fromthe value ofLDR First,LDR Second,or LDRFourth.

Networkplanning

LDR Fourth LDRFOUH(BSC6900,BSC6910)

BSC6900/BSC6910

If this parameteris set to a valueother thanCLOSE, ensurethat the value isdifferent fromthe value ofLDR First,LDR Second,or LDR Third.

Networkplanning



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ParameterName


LDR-triggeredSecondary LinkRelease

RelFlexAbis-ForLdr(BSC6900,BSC6910)

BSC6900/BSC6910

This parameterspecifieswhether theBSC releasessecondary linkson a PDCHwhen LoadReshuffling(LDR) istriggeredbecausetransmissionresources arecongested undera BTS usingFlex Abis. If thisparameter is setto ON(On), theBSC releasessecondary linkswhen LDR istriggered. If thisparameter is setto OFF(Off),the BSC doesnot release thesecondary linkscurrently usedbut cannot applyfor subsequentsecondary links.

Networkplanning



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ParameterName


UL CodingScheme Adj. forSecondary LinkRelease

UlCsAdjForAbisRel(BSC6900,BSC6910)

BSC6900/BSC6910

This parameterspecifieswhether theBSC adjustsuplink codingschemes in realtime afterreleasingsecondary linkson a PDCH. Ifthis parameter isset to ON(On),the BSC adjustsuplink codingschemes in realtime. If thisparameter is setto OFF(Off),the BSC doesnot adjust uplinkcoding schemesin real time.Set thisparameter toON(On) ifLDR-triggeredSecondaryLink Release isset to ON(On).

Networkplanning

6.4.3 Feature Activation

Using the LMT

CAUTIONActivate the Flex Abis feature during off-peak hours because the following operations will causethe BTS to be out-of-service.

On the BSC LMT, perform the following steps:

Step 1 Run the DEA BTS command to deactivate a BTS.



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Step 2 Run the MOD BTS command to enable Flex Abis. In this step, set Flex Abis Mode toFLEX_ABIS(Flex Abis) and set BTS Multiplexing Mode to an appropriate value.

Step 3 Run the SET BTSFLEXABISPARA commandwith Reserved Traffic Timeslots on an E1/T1 set based on actual conditions.

Step 4 (Optional) Run the SET BSCPSSOFTPARA command with LDR-triggered Secondary LinkRelease and UL Coding Scheme Adj. for Secondary Link Release set to appropriate values.

Step 5 (Optional) To control transmission resource congestion, run the ADD TRMLOADTHcommand. In this step, set Transport Typeto TDM(TDM), and set TRM load thresholdindex, Congestion remain ratio, and Congestion clear remain ratioto appropriate values.

Step 6 (Optional) To control transmission resource congestion, run the SET BSCABISPRIMAPcommand. In this step, specify the BTS to be configured, set Carrier Type to TDM, and setTRM Load Threshold switch and TRM load threshold index to appropriate values.

NOTE

TRM load threshold index must be set to the value specified by TRM load threshold index in the ADDTRMLOADTH command.

Step 7 (Optional) To control transmission resource congestion, run the SET LDR command with LDRFirst, LDR Second, LDR Third, and LDR Fourth set to appropriate values.

NOTE

The settings of these parameters take effect for all BTSs under the BSC.

Step 8 (Optional) To ensure that CS services take preference over PS services, run the SETBSCBASIC command with Transmission Resource Preempting Support set to ON(On).

When Transmission Resource Preempting Support is set to ON(On), new high-priority CSservices can preempt the Abis timeslots occupied by ongoing low-priority CS services if all Abistimeslots have been occupied.

NOTE

The setting of this parameter takes effect for all BTSs under the BSC.

Step 9 Run the ACT BTS command to activate the BTS.

----End

MML Examples

DEA BTS: IDTYPE=BYID, BTSID=0;

MOD BTS: IDTYPE=BYID, BTSID=0, NEWNAME="bts-3900",FLEXABISMODE=FLEX_ABIS, MPMODE=MODE4_1;

SET BTSFLEXABISPARA: IDTYPE=BYID, BTSID=0, RSVTCHTSNUM=5;

ACT BTS: IDTYPE=BYID, BTSID=0, ACTTYPE=ACTALL;

Using the CME

This feature cannot be activated by using the CME.



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6.4.4 Activation ObservationStep 1 Run the LST BTSPORTTS command. In this step, set BTS In Port NO. to the number of the

port that connects the BTS to the BSC, Port Direction to the same direction as the BTS, andTS Type to ALL(ALL).

Step 2 Run the SET BTSFORBIDTS command to block Flex Abis timeslots until only fourconsecutive 16 kbit/s sub-timeslots are used for Flex Abis. In this step, set Start TimeslotNo., Start Sub Timeslot No., End Timeslot NO., and End Sub Timeslot NO. according tothe timeslot number and sub-timeslot number of Flex Abis timeslots.

NOTE

Block only Flex Abis timeslots. Reserve only one 64 kbit/s sub-timeslot for services because timeslots areblocked in units of 64 kbit/s sub-timeslots.

Step 3 Run the DEA GCELL command with Cell Index set to the index of the cell to be blocked.Repeat this step until only one cell is unblocked under the BTS.

Step 4 Run the SET GTRXCHANADMSTAT command. In this step, set Channel No. to the numberof the channel to be blocked, and Administrative State to Lock(Lock). Repeat this step untilthe unblocked cell has only the BCCH, one SDCCH, and four TCHs left unblocked.

Step 5 Use four test MSs to call a fixed-line phone in the cell and maintain the call.

Step 6 Run the DSP ABISTS command to check the timeslot status. In this step, specify SubrackNo., Slot No., and Port No., and set State to OCCUPIED(OCCUPIED). The Flex Abis timeslotcorresponding to the TCH occupied by the call is the timeslot that is unblocked.

Step 7 Hang up the call and block the occupied TCH by performing Step 4. Then, unblock the otherfour TCHs.

Step 8 Use four test MSs to call a fixed-line phone in the cell and maintain the call.

Step 9 Run the DSP ABISTS command to check the timeslot status. In this step, specify SubrackNo., Slot No., and Port No., and set State to OCCUPIED(OCCUPIED). The Flex Abis timeslotcorresponding to the TCH occupied by the call is the timeslot that is unblocked.

Step 10 Release the call.

----End

6.4.5 Deactivation

Using the LMT

CAUTIONDeactivate the Flex Abis feature during off-peak hours because the following operations willcause the BTS to be out-of-service.

Step 1 Run the DEA BTS command to deactivate the BTS.

Step 2 Run the MOD BTS command with Flex Abis Mode set to FIX_16K_ABIS(Fix Abis).



25

Step 3 Run the ACT BTS command to activate the BTS.

----End

MML ExamplesDEA BTS: IDTYPE=BYID, BTSID=0;

MOD BTS: IDTYPE=BYID, BTSID=0, NEWNAME="bts-3900",FLEXABISMODE=FIX_16K_ABIS;

ACT BTS: IDTYPE=BYID, BTSID=0, ACTTYPE=ACTALL;

Using the CMEThis feature cannot be deactivated by using the CME.

6.5 Performance Optimization

MonitoringTransmission resources are congested if the values of the following counters are not 0:

l SITE.8K.ASS.FAIL.RATE Congestion Rate of Dynamic Resource Assignment (8 kbit/s)l SITE.16K.ASS.FAIL.RATE Congestion Rate of Dynamic Resource Assignment (16 kbit/

s)

If transmission resources are congested frequently, configure more transmission links to expandthe network capacity.

Parameter OptimizationNone

6.6 TroubleshootingNone



26

7 Parameters

Table 7-1 Parameter description

Parameter ID NE MMLCommand

Feature ID Feature Name Description

MPMODE BSC6900 ADD BTSMOD BTS

GBFD-111301GBFD-117301GBFD-117801

LAPDMultiplexing atAbis InterfaceFlex AbisRing Topology

Meaning:Timeslot multiplexingmode at the Abisinterface of theBTS. The BTSsupports twomultiplexingmodes:statisticalmultiplexing ona 64 kbit/stimeslot andphysicalmultiplexing ona 16 kbit/stimeslot. Thefirst mode isfurtherclassified intothe following sixtypes: 1:1, 2:1,3:1, 4:1, 5:1, and6:1. A BTSsupports thefollowing sixtypes of timeslotobjects: OML:operation andmaintenancelink of the BTS.Each BTS hasonly one OML.

GSM BSSFlex Abis Feature Parameter Description 7 Parameters


27



In the case ofstatisticalmultiplexing ona 64 kbit/stimeslot, theOML works at64 kbit/s. In thiscase, the OMLcan bemultiplexedonly with thesignaling linksin the samecabinet group ofthe BTS. In thecase of physicalmultiplexing ona 16 kbit/stimeslot, theOML works at16 kbit/s. In thiscase, the OMLuses a 16 kbit/stimeslot. ESL:extendedsignaling link ofthe BTS. If theBTS supportsFlex Abis, in thecase ofstatisticalmultiplexing ona 64 kbit/stimeslot, a 64kbit/s timeslotneeds to beassigned to theESL. In thiscase, the ESL isalwaysmultiplexedwith the OML inthe 64 kbit/stimeslot. In thecase of physicalmultiplexing ona 16 kbit/stimeslot, notimeslot is



28



assigned to theESL. In thiscase, the ESLshares the sametimeslot with theOML. RSL:radio signalinglayer link in eachTRX. Each TRXhas one RSL. Inthe case ofstatisticalmultiplexing ona 64 kbit/stimeslot, theRSL works at 64kbit/s. In thiscase, the RSLcan bemultiplexedonly with thesignaling linksin the samecabinet group ofthe BTS. In thecase of physicalmultiplexing ona 16 kbit/stimeslot, theRSL works at 16kbit/s. In thiscase, the RSLuses a 16 kbit/stimeslotexclusively.TCH: trafficchannels in eachTRX. The TCHworks at 16 kbit/s. Idle: idletimeslots of theBTS. An idletimeslot worksat 16 kbit/s. Inthe case ofstatisticalmultiplexing ona 64 kbit/stimeslot, the idle



29



timeslots can bemultiplexedonly with theTCHs in thesame cabinetgroup onto one64 kbit/stimeslot. Semi:monitoringtimeslots of theBTS. Themonitoringtimeslots workat 8 kbit/s, 16kbit/s, 32 kbit/s,and 64 kbit/s.The monitoringtimeslots can bemultiplexedonly with semi-permanent links.A 2048 kbit/s E1contains thirty-two 64 kbit/stimeslots.Timeslot 0 isreserved forsynchronizationand cannot beassigned.Statisticalmultiplexingmeans thatsignalingtimeslots aretime-divisionmultiplexed inan E1 timeslot,such as the OMLand RSLtimeslots or theRSL timeslots.For example, inthe case of 4:1multiplexing,one 64 kbit/stimeslotmultiplexes oneOML and three



30



RSLs or fourRSLs of theBTS. The 64kbit/s timeslotthat multiplexesthe OML has amultiplexingratio of up to 4:1even if themultiplexingratio exceeds4:1. HDLC andIP BTS do notsupport thisparameter.When themultiplexingratio of BTS isconfigured 4:1,"MR.Preprocessing" isautomaticallyadjusted toBTS_Preprocessing, "SentFreq.ofpreprocessedMR" isautomaticallyadjusted to Onceevery second.When othermultiplexingratio isconfigured,"MR.Preprocessing" isautomaticallyadjusted toBSC_Preprocessing, "SentFreq.ofpreprocessedMR" isautomaticallyadjusted to Onceevery twosecond. eGBTS



31



do not supportthis parameter.GUI ValueRange:MODE1_1, MODE2_1,MODE3_1,MODE4_1,MODE5_1,MODE6_1,MODE16KUnit:NoneActual ValueRange:MODE1_1, MODE2_1,MODE3_1,MODE4_1,MODE5_1,MODE6_1,MODE16KDefaultValue:MODE4_1



32



MPMODE BSC6910 ADD BTSMOD BTS

GBFD-111301GBFD-117301GBFD-117801

LAPDMultiplexing atAbis InterfaceFlex AbisRing Topology

Meaning:Timeslot multiplexingmode at the Abisinterface of theBTS. The BTSsupports twomultiplexingmodes:statisticalmultiplexing ona 64 kbit/stimeslot andphysicalmultiplexing ona 16 kbit/stimeslot. Thefirst mode isfurtherclassified intothe following sixtypes: 1:1, 2:1,3:1, 4:1, 5:1, and6:1. A BTSsupports thefollowing sixtypes of timeslotobjects: OML:operation andmaintenancelink of the BTS.Each BTS hasonly one OML.In the case ofstatisticalmultiplexing ona 64 kbit/stimeslot, theOML works at64 kbit/s. In thiscase, the OMLcan bemultiplexedonly with thesignaling linksin the samecabinet group ofthe BTS. In thecase of physicalmultiplexing on



33



a 16 kbit/stimeslot, theOML works at16 kbit/s. In thiscase, the OMLuses a 16 kbit/stimeslot. ESL:extendedsignaling link ofthe BTS. If theBTS supportsFlex Abis, in thecase ofstatisticalmultiplexing ona 64 kbit/stimeslot, a 64kbit/s timeslotneeds to beassigned to theESL. In thiscase, the ESL isalwaysmultiplexedwith the OML inthe 64 kbit/stimeslot. In thecase of physicalmultiplexing ona 16 kbit/stimeslot, notimeslot isassigned to theESL. In thiscase, the ESLshares the sametimeslot with theOML. RSL:radio signalinglayer link in eachTRX. Each TRXhas one RSL. Inthe case ofstatisticalmultiplexing ona 64 kbit/stimeslot, theRSL works at 64kbit/s. In this



34



case, the RSLcan bemultiplexedonly with thesignaling linksin the samecabinet group ofthe BTS. In thecase of physicalmultiplexing ona 16 kbit/stimeslot, theRSL works at 16kbit/s. In thiscase, the RSLuses a 16 kbit/stimeslotexclusively.TCH: trafficchannels in eachTRX. The TCHworks at 16 kbit/s. Idle: idletimeslots of theBTS. An idletimeslot worksat 16 kbit/s. Inthe case ofstatisticalmultiplexing ona 64 kbit/stimeslot, the idletimeslots can bemultiplexedonly with theTCHs in thesame cabinetgroup onto one64 kbit/stimeslot. Semi:monitoringtimeslots of theBTS. Themonitoringtimeslots workat 8 kbit/s, 16kbit/s, 32 kbit/s,and 64 kbit/s.The monitoring



35



timeslots can bemultiplexedonly with semi-permanent links.A 2048 kbit/s E1contains thirty-two 64 kbit/stimeslots.Timeslot 0 isreserved forsynchronizationand cannot beassigned.Statisticalmultiplexingmeans thatsignalingtimeslots aretime-divisionmultiplexed inan E1 timeslot,such as the OMLand RSLtimeslots or theRSL timeslots.For example, inthe case of 4:1multiplexing,one 64 kbit/stimeslotmultiplexes oneOML and threeRSLs or fourRSLs of theBTS. The 64kbit/s timeslotthat multiplexesthe OML has amultiplexingratio of up to 4:1even if themultiplexingratio exceeds4:1. IP BTS donot support thisparameter.When themultiplexingratio of BTS is



36



configured 4:1,"MR.Preprocessing" isautomaticallyadjusted toBTS_Preprocessing, "SentFreq.ofpreprocessedMR" isautomaticallyadjusted to Onceevery second.When othermultiplexingratio isconfigured,"MR.Preprocessing" isautomaticallyadjusted toBSC_Preprocessing, "SentFreq.ofpreprocessedMR" isautomaticallyadjusted to Onceevery twosecond. eGBTSdo not supportthis parameter.GUI ValueRange:MODE1_1, MODE2_1,MODE3_1,MODE4_1,MODE5_1,MODE6_1,MODE16KUnit:NoneActual ValueRange:MODE1_1, MODE2_1,MODE3_1,MODE4_1,MODE5_1,



37



MODE6_1,MODE16KDefaultValue:MODE4_1



38



FLEXABISMODE

BSC6900 ADD BTSMOD BTS

GBFD-117301 Flex Abis Meaning:Service timeslotassignmentmode for theBTS. If thisparameter is settoFIX_16K_ABIS, the BSCassigns a fixedAbistransmissiontimeslot to aTCH. If thisparameter is setto FLEX_ABIS,the BSC assignsan Abistransmissiontimeslotdynamically to aTCH (except thestatic PDCH) toincrease theresourceutilization. Ifthis parameter isset toSEMI_ABIS,the BTS towhich a TCHbelongs assignsa fixed Abistransmissiontimeslot to theTCH while theupper-level BTSset toFLEX_ABISassigns an Abistransmissiontimeslotdynamically tothe TCH. Thismode applieswhere old andnew BTSs arecascaded.HDLC and IP



39



BTSs do notsupport thisparameter. 1. Ifthe Flex Abisfunction isenabled on theBTS, and if theextensioncabinet group isdirectlyconnected to theBSC, the Abistimeslotsallocated to theextensioncabinet groupare displayed asTCH, indicatingfixed timeslots.If the extensioncabinet groupneeds to processdata services,and if the high-rate codingschemes (CS3and CS4; MCS3to MCS9) arerequired, idletimeslots need tobe configured. 2.If the Flex Abisfunction isenabled on theBTS, and if thechannel type ischanged to staticPDCH, the typeofcorrespondingAbis timeslots isautomaticallychanged toTCH, indicatingfixed timeslots.3. In the case ofcascaded BTSs,if an upper-levelBTS is in Flex



40



Abis mode, andif a lower-levelBTS is inSemiSolidmode, the typeof the timeslotsallocated to thelower BTS isdisplayed asTCH, indicatingfixed timeslots,but the timeslottype that theupper-level BTSreports to theBSC isdisplayed asFlex. If thelower-level BTSneeds to processdata services,and if the high-rate codingschemes (CS3and CS4; MCS3to MCS9) arerequired, idletimeslots need tobe configured. 4.eGBTS do notsupport thisparameter.GUI ValueRange:FIX_16K_ABIS(FixAbis),FLEX_ABIS(Flex Abis),SEMI_ABIS(SemisolidAbis)Unit:NoneActual ValueRange:FIX_16K_ABIS,FLEX_ABIS,SEMI_ABIS



41



DefaultValue:FIX_16K_ABIS(FixAbis)



42



FLEXABISMODE

BSC6910 ADD BTSMOD BTS

GBFD-117301 Flex Abis Meaning:Service timeslotassignmentmode for theBTS. If thisparameter is settoFIX_16K_ABIS, the BSCassigns a fixedAbistransmissiontimeslot to aTCH. If thisparameter is setto FLEX_ABIS,the BSC assignsan Abistransmissiontimeslotdynamically to aTCH (except thestatic PDCH) toincrease theresourceutilization. Ifthis parameter isset toSEMI_ABIS,the BTS towhich a TCHbelongs assignsa fixed Abistransmissiontimeslot to theTCH while theupper-level BTSset toFLEX_ABISassigns an Abistransmissiontimeslotdynamically tothe TCH. Thismode applieswhere old andnew BTSs arecascaded. IPBTSs do not



43



support thisparameter. 1. Ifthe Flex Abisfunction isenabled on theBTS, and if theextensioncabinet group isdirectlyconnected to theBSC, the Abistimeslotsallocated to theextensioncabinet groupare displayed asTCH, indicatingfixed timeslots.If the extensioncabinet groupneeds to processdata services,and if the high-rate codingschemes (CS3and CS4; MCS3to MCS9) arerequired, idletimeslots need tobe configured. 2.If the Flex Abisfunction isenabled on theBTS, and if thechannel type ischanged to staticPDCH, the typeofcorrespondingAbis timeslots isautomaticallychanged toTCH, indicatingfixed timeslots.3. In the case ofcascaded BTSs,if an upper-levelBTS is in FlexAbis mode, and



44



if a lower-levelBTS is inSemiSolidmode, the typeof the timeslotsallocated to thelower BTS isdisplayed asTCH, indicatingfixed timeslots,but the timeslottype that theupper-level BTSreports to theBSC isdisplayed asFlex. If thelower-level BTSneeds to processdata services,and if the high-rate codingschemes (CS3and CS4; MCS3to MCS9) arerequired, idletimeslots need tobe configured. 4.eGBTS do notsupport thisparameter.GUI ValueRange:FIX_16K_ABIS(FixAbis),FLEX_ABIS(Flex Abis),SEMI_ABIS(SemisolidAbis)Unit:NoneActual ValueRange:FIX_16K_ABIS,FLEX_ABIS,SEMI_ABISDefaultValue:FIX_16K



45



_ABIS(FixAbis)

TDMCONGTH

BSC6900 ADDTRMLOADTH

GBFD-117301 Flex Abis Meaning:If theratio of availableTDM bandwidthis less than thisvalue,congestioncontrol istriggered.GUI ValueRange:0~100Unit:%Actual ValueRange:0~100Default Value:15

TDMCONGTH


GBFD-117301 Flex Abis Meaning:If theratio of availableTDM bandwidthis less than thisvalue,congestioncontrol istriggered.GUI ValueRange:0~100Unit:%Actual ValueRange:0~100Default Value:15



46



TDMCONGCLRTH


GBFD-117301 Flex Abis Meaning:If theratio of availableTDM bandwidthis greater than orequal to thisvalue,congestioncontrol isstopped.GUI ValueRange:0~100Unit:%Actual ValueRange:0~100Default Value:20

TDMCONGCLRTH


GBFD-117301 Flex Abis Meaning:If theratio of availableTDM bandwidthis greater than orequal to thisvalue,congestioncontrol isstopped.GUI ValueRange:0~100Unit:%Actual ValueRange:0~100Default Value:20



47



LDRFST BSC6900 SET LDR GBFD-118601GBFD-117301GBFD-118611GBFD-118605

Abis over IPFlex AbisAbis IP over E1/T1IP QOS

Meaning:Firstaction taken forload controlGUI ValueRange:CLOSE(Close),PSDOWN(PSDownspeeding),AMRC(AMRC), CSPH(CS PreferenceTCHH),CSFHHO(CSTCHF-TCHHHO)Unit:NoneActual ValueRange:CLOSE,PSDOWN,AMRC, CSPH,CSFHHODefaultValue:PSDOWN(PSDownspeeding)



48



LDRFST BSC6910 SET LDR GBFD-118601GBFD-117301GBFD-118611GBFD-118605


Meaning:Firstaction taken forload controlGUI ValueRange:CLOSE(Close),PSDOWN(PSDownspeeding),AMRC(AMRC), CSPH(CS PreferenceTCHH),CSFHHO(CSTCHF-TCHHHO)Unit:NoneActual ValueRange:CLOSE,PSDOWN,AMRC, CSPH,CSFHHODefaultValue:PSDOWN(PSDownspeeding)



49



LDRSND BSC6900 SET LDR GBFD-118601GBFD-117301GBFD-118611GBFD-118605


Meaning:Second action takenfor load controlGUI ValueRange:CLOSE(Close),PSDOWN(PSDownspeeding),AMRC(AMRC), CSPH(CS PreferenceTCHH),CSFHHO(CSTCHF-TCHHHO)Unit:NoneActual ValueRange:CLOSE,PSDOWN,AMRC, CSPH,CSFHHODefaultValue:AMRC(AMRC)



50



LDRSND BSC6910 SET LDR GBFD-118601GBFD-117301GBFD-118611GBFD-118605


Meaning:Second action takenfor load controlGUI ValueRange:CLOSE(Close),PSDOWN(PSDownspeeding),AMRC(AMRC), CSPH(CS PreferenceTCHH),CSFHHO(CSTCHF-TCHHHO)Unit:NoneActual ValueRange:CLOSE,PSDOWN,AMRC, CSPH,CSFHHODefaultValue:AMRC(AMRC)



51



LSRTRD BSC6900 SET LDR GBFD-118601GBFD-117301GBFD-118622GBFD-118605

Abis over IPFlex AbisA IP over E1/T1IP QOS

Meaning:Thirdaction taken forload controlGUI ValueRange:CLOSE(Close),PSDOWN(PSDownspeeding),AMRC(AMRC), CSPH(CS PreferenceTCHH),CSFHHO(CSTCHF-TCHHHO)Unit:NoneActual ValueRange:CLOSE,PSDOWN,AMRC, CSPH,CSFHHODefaultValue:CSPH(CS PreferenceTCHH)



52



LSRTRD BSC6910 SET LDR GBFD-118601GBFD-117301GBFD-118605

Abis over IPFlex AbisIP QOS

Meaning:Thirdaction taken forload controlGUI ValueRange:CLOSE(Close),PSDOWN(PSDownspeeding),AMRC(AMRC), CSPH(CS PreferenceTCHH),CSFHHO(CSTCHF-TCHHHO)Unit:NoneActual ValueRange:CLOSE,PSDOWN,AMRC, CSPH,CSFHHODefaultValue:CSPH(CS PreferenceTCHH)



53



LDRFOUH BSC6900 SET LDR GBFD-118601GBFD-117301GBFD-118611GBFD-118605


Meaning:Fourthaction taken forload controlGUI ValueRange:CLOSE(Close),PSDOWN(PSDownspeeding),AMRC(AMRC), CSPH(CS PreferenceTCHH),CSFHHO(CSTCHF-TCHHHO)Unit:NoneActual ValueRange:CLOSE,PSDOWN,AMRC, CSPH,CSFHHODefaultValue:CSFHHO(CS TCHF-TCHH HO)



54



LDRFOUH BSC6910 SET LDR GBFD-118601GBFD-117301GBFD-118611GBFD-118605


Meaning:Fourthaction taken forload controlGUI ValueRange:CLOSE(Close),PSDOWN(PSDownspeeding),AMRC(AMRC), CSPH(CS PreferenceTCHH),CSFHHO(CSTCHF-TCHHHO)Unit:NoneActual ValueRange:CLOSE,PSDOWN,AMRC, CSPH,CSFHHODefaultValue:CSFHHO(CS TCHF-TCHH HO)

TSCOUNT BSC6900 SETBTSIDLETS

GBFD-114101GBFD-117301

GPRSFlex Abis

Meaning:Number of idletimeslots. Youcan configure upto 128 idletimeslots for theBTS at a time. ABTS can beconfigured withup to 512 idletimeslots.GUI ValueRange:0~512Unit:NoneActual ValueRange:0~512DefaultValue:None



55



TSCOUNT BSC6910 SETBTSIDLETS

GBFD-114101GBFD-117301

GPRSFlex Abis

Meaning:Number of idletimeslots. Youcan configure upto 128 idletimeslots for theBTS at a time. ABTS can beconfigured withup to 512 idletimeslots.GUI ValueRange:0~512Unit:NoneActual ValueRange:0~512DefaultValue:None



56



RelFlexAbis-ForLdr

BSC6900 SETBSCPSSOFTPARA

GBFD-118605GBFD-117301

IP QOSFlex Abis

Meaning:Whether the BSCreleasessecondary linkson a PDCHwhen LoadReshuffling(LDR) istriggeredbecausetransmissionresources arecongested undera BTS usingFlex Abis. If thisparameter is setto ON(On), theBSC releasessecondary linkswhen LDR istriggered. If thisparameter is setto OFF(Off), theBSC does notrelease thesecondary linkscurrently usedbut cannot applyfor subsequentsecondary links.GUI ValueRange:OFF(Off), ON(On)Unit:NoneActual ValueRange:OFF, ONDefaultValue:ON(On)



57



RelFlexAbis-ForLdr


GBFD-118605GBFD-117301

IP QOSFlex Abis

Meaning:Whether the BSCreleasessecondary linkson a PDCHwhen LoadReshuffling(LDR) istriggeredbecausetransmissionresources arecongested undera BTS usingFlex Abis. If thisparameter is setto ON(On), theBSC releasessecondary linkswhen LDR istriggered. If thisparameter is setto OFF(Off), theBSC does notrelease thesecondary linkscurrently usedbut cannot applyfor subsequentsecondary links.GUI ValueRange:OFF(Off), ON(On)Unit:NoneActual ValueRange:OFF, ONDefaultValue:ON(On)



58



UlCsAdjForAbisRel


GBFD-114201GBFD-114101

EGPRSGPRS

Meaning:Whether the BSCadjusts uplinkcoding schemesin real time afterreleasingsecondary linkson a PDCH. Ifthis parameter isset to ON, theBSC adjustsuplink codingschemes in realtime. If thisparameter is setto OFF, the BSCdoes not adjustuplink codingschemes in realtime.GUI ValueRange:OFF(Off), ON(On)Unit:NoneActual ValueRange:OFF, ONDefaultValue:OFF(Off)



59



UlCsAdjForAbisRel


GBFD-114201GBFD-114101

EGPRSGPRS

Meaning:Whether the BSCadjusts uplinkcoding schemesin real time afterreleasingsecondary linkson a PDCH. Ifthis parameter isset to ON, theBSC adjustsuplink codingschemes in realtime. If thisparameter is setto OFF, the BSCdoes not adjustuplink codingschemes in realtime.GUI ValueRange:OFF(Off), ON(On)Unit:NoneActual ValueRange:OFF, ONDefaultValue:OFF(Off)



60



RSVTCHTSNUM

BSC6900 SETBTSFLEXABISPARA

GBFD-117301 Flex Abis Meaning:Number of 64 kbit/stimeslots forTCH, dynamicPDCH, orsecondary linkson an E1/T1.These timeslotsdo not includethe timeslots forOML, ESL,RSL, and staticPDCH, fixedly-configured idletimeslots,monitoringtimeslots, andtransparenttimeslots.GUI ValueRange:0~30Unit:NoneActual ValueRange:0~30Default Value:0



61



RSVTCHTSNUM

BSC6910 SETBTSFLEXABISPARA

GBFD-117301 Flex Abis Meaning:Number of 64 kbit/stimeslots forTCH, dynamicPDCH, orsecondary linkson an E1/T1.These timeslotsdo not includethe timeslots forOML, ESL,RSL, and staticPDCH, fixedly-configured idletimeslots,monitoringtimeslots, andtransparenttimeslots.GUI ValueRange:0~30Unit:NoneActual ValueRange:0~30Default Value:0



62



ENPREEMPTTRANSADMT

BSC6900 SETBSCBASIC

GBFD-118605 IP QOS Meaning:Whenthis parameter isset to "ON", ifthere are noavailable Abistransmissionresources, ahigh-priorityuser canpreempt thetransmissionresources of alow-priorityuser. If thepreemptionsucceeds, a calldrop occurs atthe low-priorityuser.GUI ValueRange:OFF(Off), ON(On)Unit:NoneActual ValueRange:OFF, ONDefaultValue:ON(On)



63



ENPREEMPTTRANSADMT

BSC6910 SETBSCBASIC

GBFD-118605 IP QOS Meaning:Whenthis parameter isset to "ON", ifthere are noavailable Abistransmissionresources, ahigh-priorityuser canpreempt thetransmissionresources of alow-priorityuser. If thepreemptionsucceeds, a calldrop occurs atthe low-priorityuser.GUI ValueRange:OFF(Off), ON(On)Unit:NoneActual ValueRange:OFF, ONDefaultValue:ON(On)

TRANST BSC6900 ADDTRMLOADTH

GBFD-118605GBFD-117301

IP QOSFlex Abis

Meaning:Trans-port type.GUI ValueRange:IP(IP),HDLC(HDLC),TDM(TDM)Unit:NoneActual ValueRange:IP,HDLC, TDMDefaultValue:None



64



TRANST BSC6910 ADDTRMLOADTH

GBFD-118605GBFD-117301

IP QOSFlex Abis

Meaning:Trans-port type.GUI ValueRange:IP(IP),TDM(TDM)Unit:NoneActual ValueRange:IP, TDMDefaultValue:None

LOADTHSW BSC6900 SETBSCABISPRIMAP

GBFD-111202 O&M of BTS Meaning:TRMload thresholdswitch.GUI ValueRange:OFF(OFF), ON(ON)Unit:NoneActual ValueRange:OFF, ONDefaultValue:OFF(OFF)

LOADTHSW BSC6910 SETBSCABISPRIMAP

GBFD-111202 O&M of BTS Meaning:TRMload thresholdswitch.GUI ValueRange:OFF(OFF), ON(ON)Unit:NoneActual ValueRange:OFF, ONDefaultValue:OFF(OFF)



65



TRMLOADTHINDEX

BSC6900 ADDTRMLOADTHRMVTRMLOADTH

GBFD-117301 Flex Abis Meaning:TRMload thresholdindex. It is theunique ID of theload threshold.GUI ValueRange:10~199Unit:NoneActual ValueRange:10~199DefaultValue:None

TRMLOADTHINDEX

BSC6910 ADDTRMLOADTHRMVTRMLOADTH

GBFD-117301 Flex Abis Meaning:TRMload thresholdindex. It is theunique ID of theload threshold.GUI ValueRange:10~199Unit:NoneActual ValueRange:10~199DefaultValue:None



66

8 Counters

Table 8-1 Counter description

Counter ID Counter Name CounterDescription

NE Feature ID Feature Name

1276080417 SITE.ASS.CS.8K

R2720:Numberof DynamicResourceRequests (8 kbit/s CS Service)

BSC6910 GBFD-117301 Flex Abis

1276080418 SITE.ASS.CS.16K

R2721:Numberof DynamicResourceRequests (16kbit/s CSService)


1276080419 SITE.ASS.PS.MAIN.LNK

R2722:Numberof DynamicResourceRequests (PSMain Link)


1276080420 SITE.ASS.PS.SUB.LNK

R2723:Numberof DynamicResourceRequests (PSSublink)


1276080421 SITE.ASS.FAIL.CS.8K

R2730:Numberof FailedDynamicResourceRequests (8 kbit/s CS Service)


GSM BSSFlex Abis Feature Parameter Description 8 Counters


67




R2731:Numberof FailedDynamicResourceRequests (16kbit/s CSService)


1276080423 SITE.ASS.FAIL.PS.MAIN.LNK

R2732:Numberof FailedDynamicResourceRequests (PSMain Link)


1276080424 SITE.ASS.FAIL.PS.SUB.LNK

R2733:Numberof FailedDynamicResourceRequests (PSSublink)


1276080425 SITE.FLEX.TS.NUM

R2741:Numberof AvailableFlex Timeslots


1276080426 SITE.FAULT.FLEX.TS.NUM

R2742:Numberof Faulty FlexTimeslots


1276080427 SITE.8K.ASS.FAIL.RATE

RR2751:Congestion Rate ofDynamicResourceAssignment (8kbit/s)





1276080429 SITE.LNK.FAIL.CS

R276:Numberof Failed CSConnectionsCaused by LinkFailure




68



1276769417 BS.RES.USE.ABIS.AVG

L1151A:Meannumber ofoccupiedtimeslots on theAbis interface


1278474444 CELL.ABIS.ALLOC.REQ.TIMES.FR

R3162A:Number of Requests forAllocating AbisResources(TCHF)


1278474445 CELL.ABIS.ALLOC.REQ.TIMES.HR

R3163A:Number of Requests forAllocating AbisResources(TCHH)


1278474446 CELL.ABIS.ALLOC.REQ.TIMES.PDCH

R3164A:Number of Requests forAllocating AbisResources(DynamicPDCH)


1278476435 CELL.ABIS.ALLOC.FAIL.TIMES.FR

R3162B:Number of Failures toAllocate AbisResources(TCHF)


1278476436 CELL.ABIS.ALLOC.FAIL.TIMES.HR

R3163B:Number of Failures toAllocate AbisResources(TCHH)


1278476437 CELL.ABIS.ALLOC.FAIL.TIMES.PDCH

R3164B:Number of Failures toAllocate AbisResources(DynamicPDCH)


1282412072 SITE.CS.USED.TS.RATE

T66001:Timeslot UtilizationRate of CSService In a BTS




69



1282412075 SITE.PS.USED.TS.RATE

T66002:Timeslot UtilizationRate of PSService In a BTS


1282431743 SITE.CS.ALLOCATED.TS.NUM.MAX

T66005:Maximum Number ofTimeslotsOccupied by CSServices


1282431744 SITE.PS.ALLOCATED.TS.NUM.MAX

T66006:Maximum Number ofTimeslotsOccupied by PSServices


1282431745 SITE.TOTAL.ALLOCATED.TS.NUM.MAX

T66007:Maximum Number ofOccupied FlexTimeslots


1282449293 SITE.CS.ALLOCATED.TS.NUM.AVR

T66003:Average Number ofTimeslotsOccupied by CSServices


1282449294 SITE.PS.ALLOCATED.TS.NUM.AVR

T66004:Average Number ofTimeslotsOccupied by PSServices


1282449295 SITE.FLEX.TS.NUM.AVR

T66008:Average Number ofAvailable FlexTimeslots


1276080417 SITE.ASS.CS.8K

R2720:Numberof DynamicResourceRequests (8 kbit/s CS Service)


1276080418 SITE.ASS.CS.16K

R2721:Numberof DynamicResourceRequests (16kbit/s CSService)




70



1276080419 SITE.ASS.PS.MAIN.LNK

R2722:Numberof DynamicResourceRequests (PSMain Link)


1276080420 SITE.ASS.PS.SUB.LNK

R2723:Numberof DynamicResourceRequests (PSSublink)



R2730:Numberof FailedDynamicResourceRequests (8 kbit/s CS Service)



R2731:Numberof FailedDynamicResourceRequests (16kbit/s CSService)


1276080423 SITE.ASS.FAIL.PS.MAIN.LNK

R2732:Numberof FailedDynamicResourceRequests (PSMain Link)


1276080424 SITE.ASS.FAIL.PS.SUB.LNK

R2733:Numberof FailedDynamicResourceRequests (PSSublink)


1276080425 SITE.FLEX.TS.NUM

R2741:Numberof AvailableFlex Timeslots


1276080426 SITE.FAULT.FLEX.TS.NUM

R2742:Numberof Faulty FlexTimeslots




71









1276080429 SITE.LNK.FAIL.CS

R276:Numberof Failed CSConnectionsCaused by LinkFailure


1276769417 BS.RES.USE.ABIS.AVG

L1151A:Meannumber ofoccupiedtimeslots on theAbis interface


1278474444 CELL.ABIS.ALLOC.REQ.TIMES.FR

R3162A:Number of Requests forAllocating AbisResources(TCHF)


1278474445 CELL.ABIS.ALLOC.REQ.TIMES.HR

R3163A:Number of Requests forAllocating AbisResources(TCHH)


1278474446 CELL.ABIS.ALLOC.REQ.TIMES.PDCH

R3164A:Number of Requests forAllocating AbisResources(DynamicPDCH)


1278476435 CELL.ABIS.ALLOC.FAIL.TIMES.FR

R3162B:Number of Failures toAllocate AbisResources(TCHF)




72



1278476436 CELL.ABIS.ALLOC.FAIL.TIMES.HR

R3163B:Number of Failures toAllocate AbisResources(TCHH)


1278476437 CELL.ABIS.ALLOC.FAIL.TIMES.PDCH

R3164B:Number of Failures toAllocate AbisResources(DynamicPDCH)


1282412072 SITE.CS.USED.TS.RATE

T66001:Timeslot UtilizationRate of CSService In a BTS


1282412075 SITE.PS.USED.TS.RATE

T66002:Timeslot UtilizationRate of PSService In a BTS


1282431743 SITE.CS.ALLOCATED.TS.NUM.MAX

T66005:Maximum Number ofTimeslotsOccupied by CSServices


1282431744 SITE.PS.ALLOCATED.TS.NUM.MAX

T66006:Maximum Number ofTimeslotsOccupied by PSServices


1282431745 SITE.TOTAL.ALLOCATED.TS.NUM.MAX

T66007:Maximum Number ofOccupied FlexTimeslots


1282449293 SITE.CS.ALLOCATED.TS.NUM.AVR

T66003:Average Number ofTimeslotsOccupied by CSServices


1282449294 SITE.PS.ALLOCATED.TS.NUM.AVR

T66004:Average Number ofTimeslotsOccupied by PSServices




73



1282449295 SITE.FLEX.TS.NUM.AVR

T66008:Average Number ofAvailable FlexTimeslots




74

9 Glossary

For the acronyms, abbreviations, terms, and definitions, see Glossary.

GSM BSSFlex Abis Feature Parameter Description 9 Glossary


75

10 Reference Documents

There are no specific reference documents associated with this feature.

GSM BSSFlex Abis Feature Parameter Description 10 Reference Documents


76