GSM/EDGE BSS, Rel. RG20(BSS), Operating Documentation, Issue 09 Feature description BSS21335:...

GSM/EDGE BSS, Rel. RG20(BSS), Operating Documentation, Issue 09

Feature description

BSS21335: Precise Paging

DN0988098

Issue 01AApproval Date 2011-11-12

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Table of contentsThis document has 24 pages.

Summary of changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

1 Introduction to Precise Paging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2 Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82.1 End user benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82.2 Operator benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

3 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.1 Software requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.2 Hardware requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4 Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104.1 Paging method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104.2 Paging scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114.3 Repaging scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114.4 Mobile location database . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114.5 TMSI optimization for repaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

5 System impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.1 Relations to other features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.2 Impacts on A interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.3 Impacts on Air interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.4 Impacts on PCUSIG interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145.5 Impacts on BSC-NetAct interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145.6 Impacts on system performance and capacity. . . . . . . . . . . . . . . . . . . . 14

6 User interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156.1 Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156.2 MML commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166.3 System responses to failures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176.4 Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176.5 Measurements and counters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186.5.1 New counters for: 003 - Resource Access Measurement . . . . . . . . . . . 186.5.2 Key performance indicator (KPI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

7 Activating and configuring Precise Paging. . . . . . . . . . . . . . . . . . . . . . . 207.1 Activating and configuring Precise Paging. . . . . . . . . . . . . . . . . . . . . . . 217.2 Deactivating Precise Paging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

8 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 – Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

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List of tablesTable 1 Software requirements for Precise Paging . . . . . . . . . . . . . . . . . . . . . . . 9Table 2 Hardware requirements for Precise Paging . . . . . . . . . . . . . . . . . . . . . . . 9Table 3 Location database capacity (subscribers) of different BSCs . . . . . . . . . 12Table 4 New parameters for Precise Paging . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Table 5 DX error codes for Precise Paging . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Table 6 Alarms for Precise Paging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Table 7 New counters for 003 - Resource Access Measurement . . . . . . . . . . . . 18

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BSS21335: Precise Paging Summary of changes


Summary of changes Changes between document issues are cumulative. Therefore, the latest document issue contains all changes made to previous issues.

Changes in issues 01A (2011/11/12 RG20(BSS)) to issues 01 (2011/08/19 RG20(BSS))The term host BCSU have been changed to hosting signalling unit (BCSU) in Relations to other features and Impacts on PCUSIG interface sections.

Changes in issues 01 (2011/08/19 RG20(BSS))First issue.

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Summary of changes

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BSS21335: Precise Paging Introduction to Precise Paging

Id:0900d80580848058Confidential

1 Introduction to Precise PagingMost of the mobile users have low mobility and typically spends a lot of time in relatively small areas like home, work-place, campus, shopping mall, and so on. This kind of behavior increases the probability of the Mobile Station (MS) or mobile device to be suc-cessfully paged again from the same cell or its neighboring cells. Paging is a procedure by which a mobile network attempts to reach the MS or a mobile device, before any other network-initiated procedure can take place. BSC normally sends paging to all the cells belonging to the Location Area (LA) or Routing area (RA) where the MS is regis-tered. All the cells where the MS is not present receives a paging that is useless.

Continuously growing use of data services like e-mail, instant messaging, multipart games or text messages generate frequent pages. Usually, an active user can be paged from the same area.

The BSS21335: Precise Paging feature enhances the signaling capacity on the Common Control Channel (CCCH) in the Air interface. This feature solves the bottle-neck of granting access for signaling capacity on a CCCH channel, improves paging capacity, and prevents paging overload. In this feature, the MS paging messages are sent initially only towards the cell and its immediate neighbors where the MS had the last connection to BSC, instead of the whole Location Area (LA) or Routing Area (RA). Details of the cell and its neighboring cells are retrieved from the cell level location register kept by the BSC. If the MS does not response to BSC within 2 to 8 seconds, then the BSC pages rest of the cells in the original paging area (LA or RA).

Precise paging feature works in the same way as BSS21324: Intelligent Selective Paging. It allows to send a paging request to the cell where the MS is expected and to its adjacent cells within the same location area. The difference is that Precise Paging considers both CS (circuit switch) and PS (packet switch) calls to keep track on MS location while in BSS21324: Intelligent Selective Paging only the CS calls are consid-ered.

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Benefits

2 Benefits

2.1 End user benefitsEnd user experiences quality usage in terms of reduced latency. For example, in Push to Talk over Cellular (PoC) and messenger.

2.2 Operator benefitsA significant increase in the CCCH capacity is achieved, in the region of up to 50 to 70%. The gain is higher for larger LA or RA, in comparison to the same length of the neigh-boring cell list. Therefore, the load due to LA and RA updates are also optimized without compromising those due to the paging capacity.

The increase in paging capacity may be experienced as: • Fewer and possibly larger sites can be used • Reduced Abis signaling load in CCCH TRX • Reduced probability of paging overload

Compared to BSS21324: Intelligent Selective Paging feature, Precise Paging feature also provides gains for PS (packet switch) paging, which may be higher in some cells than the CS (circuit switch) paging load.

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BSS21335: Precise Paging Requirements


3 RequirementsYou need a valid license in the BSC for the feature BSS1335: Precise Paging. The feature works only for PS pagings on cells that are served by PCU2s.

3.1 Software requirements

3.2 Hardware requirements

Network element Required software release

BSC S15 EP1.2

NetAct OSS 5.3 CD3

Table 1 Software requirements for Precise Paging

Network element Required hardware

BSC BSCi, BSC2i, BSC3i, FlexiBSC

BTS Flexi (EDGE and Multiradio), Ultra, Metro BTS site, BTSplus, and Horizon BTS

PCU PCU2

Table 2 Hardware requirements for Precise Paging

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Functional description

4 Functional descriptionThe BSS212335: Precise Paging is license controlled and it has three states, OFF, ON, and CONF. It is an optional feature for the network. The Precise Paging feature is under TRX capacity type of licence and is activated in cell/segment level. It is possible to have at maximum as many Precise Paging enabled TRXs as the licence allows. Licence is needed for all unlocked TRXs in a segment. This feature can be activated to work for CS pagings or PS pagings only or both at the same time in each segment.

When Precise Paging license state is set to either “CONF” or “ON”, the BSC keeps location record of the MS. When license state is “ON”, paging message is sent initially only towards the cell, where the MS had the last connection to BSC and its immediate neighbor cells instead of the whole LA or RA. If there is no immediate paging response (within 2 to 8 seconds) after paging the cells, then rest of the cells in the original paging area (either in LA or RA) are paged. The paging response duration is configured using the Precise Paging Expanding Delay (PRECPD) parameter. The default value is 2 seconds. MS location gets updated at the end of each CS connection and when first TBF is created for PS connection. Location can be updated only when IMSI is available in BSC. IMSI is received for CS connection from MSC in Common ID message and for PS connection from SGSN in DL-UNITDATA or RA-CAPABILITY-UPDATE-ACK message.

g In the current release, PCU1 does not support Precise Paging. Also, the feature cannot be activated if even one PCU1 is in the same track where PCU2 is located in the serving cell. However, PCU type does not affect feature activation for CS paging.

This chapter is divided into the following sections: • “Paging method” • “Paging scenarios” • “Repaging scenarios” • “Mobile location database” • “TMSI optimization for repaging”

4.1 Paging methodPrecise Paging is supported with the following paging methods: • via A-interface:

To activate Precise Paging feature one of the following paging methods must be configured in MSC. • MCC + MNC + LAC • LAC • LAC + CI with Intelligent Selective Paging active in the MSC (one cell identified

in a paging message). • via Gb-interface:

To activate Precise Paging feature one of the following paging methods must be configured in SGSN. • MCC + MNC + LAC • MCC + MNC + RAC

g MCC (Mobile Country Code)

MNC (Mobile Network Code)

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BSS21335: Precise Paging Functional description


LAC (Location Area Code)

CI (Cell Identity)

RAC (Routing Area Code)

MSC (Mobile Services Switching Center)

4.2 Paging scenariosThe feature supports the following paging scenarios: • If the feature is not active in the cell but MS last known location to BSC is available,

then normal paging is applied for the MS.

g The feature can be switched off in a cell level. There are cells in the network where the feature may not be so useful, like in a railway or subway station. Even though mobile’s last known location is available, there is the possibility that the MS needs to be paged in RA or LA level since the MS may quickly move away from the Precise Paged area.

• If the MS's known location is in a cell where the Precise Paging feature is active but the feature is not active in one of its neighboring cells belonging to current precised paged area and mobile is precise paged, then the paging message is sent also to the neighboring cell where the feature is not active.

4.3 Repaging scenarios Repaging scenarios is handled by BSC via Precise Paging enabled for repagings (PRECRP) parameter. BSC handles all paging as Precise Paging or only the first paging message. Types of repaging scenarios when BSC is configured to use Precise Paging: • If Precise Paging is applied only for the first paging message received from MSC or

SGSN, then Precise Paging is applied next time for the same MS after its location has been updated in the database during next connection to the BSC.

• If Precise Paging is applied for all paging messages received from MSC and SGSN, then repaging is also made in Precise Paging mode, that is, the cell where MS location is known is first paged and its neighboring cells. If there is no response, then the paging is expanded to the rest of the cells in the LA or RA.

4.4 Mobile location databaseThere is only one location record per IMSI in BSC. When the database has got full the oldest record in the database is overwritten when a new record is stored. A record is valid for Precise Paging for maximum 24 hours. Validity is checked when the record is found during paging procedure. The maximum living time for the records is configurable between 1 – 24 hours using the Precise Paging location record living time (PRECPL ) command. 24 hours is the default value. The database is distributed in working Base Station Controller Signaling Units (BCSU)s. Each BCSU contains record of different mobiles. BCSU where location record is to be stored is calculated from IMSI. Database is copied to spare BCSU in controlled switchover. In BCSU restart or forced switchover, data in the BCSU is lost and creation of a new database in that BCSU starts from the beginning.

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Functional description

Table 3 lists the location database capacity (subscribers) of different BSCs:

4.5 TMSI optimization for repagingTMSI optimization is used for normal repaging or repaging in Precise Paging mode. BSC converts repaging sent by MSC containing only IMSI to TMSI repaging if the TMSI opti-mization for repaging is enabled using the Precise Paging TMSI optimization (PRECTO ) command. TMSI for repaging is stored from the first paging attempt which usually also contains TMSI. Instead of sending one IMSI paging in Air interface it can sent two TMSI paging. On the average 8 to 14% pages sent by MSC are repaging in live network.

When TMSI optimization is enabled, BSC’s Precise Paging MSC repaging delay (PRECMD) value is used to define the duration that TMSI needs to be stored in BSC from previous paging attempt to be used for possible next repaging attempt. Maximum time for Precise Paging MSC repaging delay parameter is 10 seconds.

BSC types Location database capacity

BSCi 120 000

BSC2i 240 000

BSC3i 660 314 000

BSC3i 1000 475 000

BSC3i 2000 950 000

FlexiBSC 3000 1 425 000

FlexiBSC 4200 1 995 000

Table 3 Location database capacity (subscribers) of different BSCs

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BSS21335: Precise Paging System impacts


5 System impactsThis chapter describes the impacts of BSS21335: Precise Paging feature on the system, other features, and existing system functionalities or properties.

This chapter is divided into the following sections: • “Relations to other features” • “Impacts on A interface” • “Impacts on Air interface” • “Impacts on PCUSIG interface” • “Impacts on BSC-NetAct interface” • “Impacts on system performance and capacity”

5.1 Relations to other featuresThe related features are as follows:

• BSS21324: Intelligent Selective PagingPrecise Paging feature works with Intelligent Selective Paging feature. If Intelligent Selective Paging feature is active in the MSC and Precise Paging feature in BSC, then the BSC initially tries to use the location information of its own database. If that is not available, then it uses the location information sent by the MSC in the paging message. BSC location information can be more accurate due to updating made during GPRS connection.

• BSS21213: Multi-operator BSS Precise Paging feature works with Multi-operator BSS feature. BSC uses Global Cell ID (MCC + MNC + LAC + CI) when MS location is saved into its database. Intelligent Selective Paging doesn’t work with Multi-operator BSS feature since MSC indicates MS’s last known cell only with LAC + Cell ID indication.

• BSS20092: Multipoint A InterfaceWhen MS is precise paged and Multipoint A Interface feature is active, then IMSI and Global CN-ID are stored in database as is done with normal paging procedure.

• BSS20738: Paging coordination in BSCPCU2 indicates to hosting signalling unit (BCSU) when a MS context has been created in PCU2 for a MS when Precise Paging feature is active. This indication is used also for Paging Coordination feature. PCU2 sends the indications to BCSU regardless Paging Coordination feature when Precise Paging feature is active.

5.2 Impacts on A interface Precise Paging decreases repagings in A interface. This is because load in Air interface gets decreased and therefore more successful pagings can be made. This is true as long as there are enough signaling resources for paging responses in the network (free Stand-alone Dedicated Control Channel (SDCCHs)).

5.3 Impacts on Air interface Paging load decreases in Air interface significantly. Precise Paging is sent at maximum to 33 cells instead of all cells in LA or RA, hence load in the Air interface gets decreased.

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System impacts

5.4 Impacts on PCUSIG interfaceSignaling load in BSC internal PCUSIG interface increases. PCU2 sends indications about MS context creations to hosting signalling unit (BCSU). The indications are sent when either Precise Paging or Paging Coordination or both the features are active. Acti-vating or deactivating the other feature while the other one is still active does not affect the signaling load.

5.5 Impacts on BSC-NetAct interfaceNetAct support new Precise Paging parameters for FBPP and SendToNW.

5.6 Impacts on system performance and capacityThis feature reduces 50 to 70% paging load in the air interface during normal traffic. Per-formance of Precise Paging feature starts to increase gradually after the feature has been switched on. The location database starts filling up with the MS's location informa-tion. Once the database has got full, the generated paging load depends directly on the count of neighboring cells defined for the cells and how often MSs are Precise Paged successfully. Precise Paged area comprises at maximum 33 cells when 32 neighbors are defined for the cell. It means that 33 pages are sent to cells first at maximum and then paging is expanded to other cells in LA/RA if needed.

For example, all cells of a BSC3i 660 can usually be in one LA or RA. Paging is normally made either in LA or RA level and the areas are usually the same size. If there are four TRXs per each cell in the BSC and 165 cells, the BSC then sends 132 paging messages less (165 – 33) to the cells when a MS is precise paged successfully as if MS would be paged in normal manner in the same LA/RA.

Savings are even higher when there are fewer neighbors defined for cell or known location is closer to LA or RA border. Paging is always conducted inside a LA or RA.

Signaling load in BSC’s internal message bus rises since paging responses and location updates are sent between BCSUs. On the other hand, broadcasted paging messages in the message bus are much shorter than the paging messages broadcasted in normal paging method.

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BSS21335: Precise Paging User interface

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6 User interfaceThis chapter is divided into the following sections: • “Parameters” • “MML commands” • “System responses to failures” • “Alarms” • “Measurements and counters”

6.1 ParametersTable 4 lists the parameters pertinent to the Precise paging feature along with its name, object class, description, range, and default value.

Name Object Description Range Default value

Precise Paging Usage

(PRECPG)

BTS With this parameter you can define whether Precise Paging is used in the cell /segment or not.

• CS pagings coming from MSC via A or Gb interface

• PS pagings received from Serving GPRS Support Node (SGSN) via Gb interface

• Both CS pagings coming from MSC via A or Gb interface and PS pagings received from SGSN via Gb interface

g When the feature is not active normal paging is applied for the MS although last known location of the MS would be in this cell.

0 (Disabled)

1 (Enabled for CS)

2 (Enabled for PS)

3 (Enabled for both CS and PS)

0 (Disabled)

Precise Paging Location Record Living Time

(PRECPL)

BSC With this parameter you can define how long BSC is allowed to use a location record of a MS for Precise Paging after creation or last update.

1 to 24 hours

24 hours

Precise Paging Expand-ing Delay (PRECPD)

BSC With this parameter you can define the delay after the paging is expanded to rest of the cells in the paging area when the MS is first Precise Paged.

2 to 8 seconds

2 seconds

Table 4 New parameters for Precise Paging

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6.2 MML commandsThe following MML commands are used to handle the Precise Paging feature: • EQC command to create BTS object.

The PRECPG (Precise Paging Usage) parameter is defined during the BTS object creation to activate Precise Paging in the cell.

• EQM command to modify BTS parameters.The PRECPG (Precise Paging Usage) parameter option is modified (Disabled (0), Enabled for CS (1), Enabled for PS (2), or Enabled for both CS and PS (3))

• EQO command to display PRECPG (Precise Paging Usage) parameter in BTS parameters execution printout.

• EEQ command to modify BSC parameters.The following precise paging parameters are modified: • PRECPL (Precise Paging Location Record Living Time) • PRECPD (Precise Paging Expanding Delay) • PRECRP (Precise Paging Enabled for Repagings) • PRECTO (Precise Paging TMSI Optimization) • PRECMD (Precise Paging MSC Repaging Delay)

Precise Paging Enabled For Repagings (PRECRP)

BSC With this parameter you can define BSC to use Precise Pagings also for repag-ings. If disabled Precise Paging is used next time for the MS after the MS’s location has been updated to BSCs location database. That happens only when the MS has connection to BSC.

g When this parameter is disabled, there may be a need to adjust repaging delay in the MSC and the SGSN.

0 (Disabled)

1 (Enabled)

1 (Enabled)

Precise Paging TMSI Optimization (PRECTO)

BSC With this parameter you can define BSC to convert repagings received with IMSI to TMSI pagings when possible.

g This feature should be disabled if MSC is configured to send repaging with TMSI.

0 (Disabled)

1 (Enabled)

0 (Disabled)

Precise Paging MSC Repaging Delay (PRECMD)

BSC With this parameter you can define the delay value used for repaging in MSC. The parameter defines for how long the BSC has to save TMSI from previous paging attempt. Recommended value is the same as repaging delay in MSC side. This parameter has effect only when Precise Paging is enabled.

1 to 10 seconds

5 seconds

Name Object Description Range Default value

Table 4 New parameters for Precise Paging (Cont.)

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• EEO command to display following precise paging parameters in BSC parameters execution printout. • PRECPL (Precise Paging Location Record Living Time) • PRECPD (Precise Paging Expanding Delay) • PRECRP (Precise Paging Enabled for Repagings) • PRECTO (Precise Paging TMSI Optimization) • PRECMD (Precise Paging MSC Repaging Delay)

6.3 System responses to failuresThis Precise Paging feature introduces the error codes shown in the following table.

6.4 AlarmsTable 6 lists the alarms associated with Precise Paging feature:

Output Name Number Description

Precise Paging feature is not in use in BSC

option_prcpg_not_in_use_ec 0065DH / 1629d

Precise paging feature is not enabled in BSC. Either the feature license is not valid or the feature status is in disabled state.

Precise Paging capacity license exceeded

prcpg_capa_lic_exceeded_ec 0065EH / 1630d

Precise paging capacity license exceeded.

Table 5 DX error codes for Precise Paging

Error ID Alarm string Fault condition

3649 Precise Paging Misconfiguration

Alarm is reported when BSC detects MSC sending repaging for the MS while BSC is still waiting paging response from the MS for the previous paging round and Precise Paging was used in paging. Alarm is set if the error happens twice or more during 5 minutes in BSC.

Alarm is cancelled if there are no errors during 5 minutes. Alarm setting is related to Precise Paging MSC repaging delay parameter in BSC and repaging delay parameter in MSC.

3652 Dynamic Memory Allocation Failure

Alarm is reported when dynamic memory allocation failed.

Table 6 Alarms for Precise Paging

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6.5 Measurements and counters

6.5.1 New counters for: 003 - Resource Access MeasurementThis section describes the measurements and counters of Precise Paging feature. The counters associated with this feature are:

6.5.2 Key performance indicator (KPI)

Frequency of Precise paging usageA new key performance indicators (KPIs) are introduced to prove precise paging feature functionality and to verify feature usage. Those check the frequency of feature usage and precise paging hit rate (probability that first paging sent to the limited group of cells is successful). The higher usage rate and the higher hit rate than the greater expected impact on performance in terms of PCH load reduction and CCCH (both PCH & AGCH) blocking decrease.

The KPIs are as follows:

PRECISE_PAGING_USAGE_RATE = 003066 PRECISE PAGING MESSAGES SENT TO BTS /(003000 PAGING MESSAGES SENT TO BTS + 003058 CS PAGING MSG SENT + 003057 PS PAGING MSG SENT)

Counter Number Description

Precise Paging Messages sent to BTS

003066 Number of PAGING COMMAND messages sent to the cell and its immedi-ate neighbors where the MS had the last connection to BSC according to Precise Paging. One of the normal paging counters 003000 PAGING MESSAGES SENT TO BTS, 003058 CS PAGING MSG SENT or 003057 PS PAGING MSG SENT is updated along with this counter according to paging type.

The counter value is updated when the PAGING COMMAND message is sent to BTS and immediate neighbors in precise paging manner.

Precise Paging Expanded

003067 Number of times when paging has been sent to the rest of the cells in the original paging area when last known location of a MS was in this cell and the MS was first Precise Paged. One of the normal paging counters 003000 PAGING MESSAGES SENT TO BTS, 003058 CS PAGING MSG SENT or 003057 PS PAGING MSG SENT is updated along with this counter.

The counter value is updated when there is no response to paging request from MS when precise paged after which the paging is expanded to rest of cells in the original paging area.

IMSI to TMSI Paging Conversion

003068 Number of times when the BSC has converted an IMSI paging message to TMSI paging message. Only paging messages received from A inter-face can be converted.

The counter value is updated when the repaging message from the MSC contains IMSI and BSC is able to convert it to TMSI paging.

Table 7 New counters for 003 - Resource Access Measurement

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PRECISE_PAGING_HIT_RATE = 003066 PRECISE PAGING MESSAGES SENT TO BTS / (003066 PRECISE PAGING MESSAGES SENT TO BTS + 003067 PRECISE PAGING EXPANDED )

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Activating and configuring Precise Paging

7 Activating and configuring Precise PagingThis chapter describes the activation and deactivation steps required for Precise paging.

• Activating and configuring Precise paging • Deactivating Precise paging

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BSS21335: Precise Paging Activating and configuring Precise Paging


7.1 Activating and configuring Precise PagingPurposeThe BSS21335: Precise Paging feature is a license key controlled software product based on TRX amount. You can activate the feature for CS pagings, PS pagings, or for both CS and PS pagings.

Prerequisites • Check the software and hardware requirements described in chapter 3 Require-

ments are installed. • Check that only PCU2 is used in the cell/segment.

1 Check that the license covering Precise Paging is installed (W7I).ZW7I:LIC,FULL:LIC=<license code>;

Example:ZW7I:LIC,FULL:LIC=1887;

For more information on licenses, see License Management in BSC.

2 Change the state of Precise Paging feature to ON (W7M).ZW7M:FEA=1887:ON;

Expected Outcome:The Precise Paging license is set to “ON”.

Unexpected Outcome:

• If the license for Precise Paging feature is not valid, then the feature cannot be acti-vated and you will get an appropriate DX error code indicating the reason of the failure.

• If dynamic memory allocation fails, then alarm “3652: Dynamic Memory Allocation Failure” is triggered.

3 Activate Precise Paging feature on segment level using (EQM)ZEQM : BTS = <BTS ID> : SEG = <SEG identification> : BMA = <BTS measure average> , CLC =<cell load for channel search, MBR =<multiband cell reporting>,.. PRECPG = <precise paging usage> <option>;

Example:ZEQM:BTS = 20:BMA=2,CLC=50,MBR=1,PRECPG=3;

Expected Outcome:Precise Paging is executed successfully and MS responds to paging.

Unexpected Outcome:

• If the precise paging license state is not “ON” and there are non “BL-USR” opera-tional state BTS(s) in the segment, then BTS modification is rejected and you will get the error code “Precise Paging feature is not in use BSC”

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Activating and configuring Precise Paging

• If license capacity check fails, then the modification is rejected and you will get the error code “Precise Paging capacity license exceeded.”

• If PCU1 is in use for the segment, then the modification is rejected and you will get the error code “Wrong PCU type.”

• If PCU2 is use for the segment but track check fails, then the modification is rejected with error code “All PCU cards in same track of BCSU should be PCU2.”

End

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BSS21335: Precise Paging Activating and configuring Precise Paging


7.2 Deactivating Precise PagingThe Precise Paging feature deactivates itself automatically when license expires or the state of the license is modified from ON to OFF/CONF.

Prerequisites • To operate the feature, the BSC is operational • Precise Paging license state is “ON” • Feature is active on the cell or segment

1 Deactivate Precise Paging feature on segment level using (EQM)ZEQM : BTS = <BTS ID> : SEG = <SEG identification> : BMA = <BTS measure average> , CLC =<cell load for channel search, MBR =<multiband cell reporting>,.. PRECPG = <precise paging usage> <option>;

Example:ZEQM:BTS = 20: BMA=2,CLC=50,MBR=1,PRECPG=0;

Expected Outcome:Precise Paging deactivation is executed successfully and MS is successfully paged in normal manner.

Unexpected Outcome:If the license for Precise Paging feature is not valid, then the feature cannot be deacti-vated and you will get an appropriate DX error code indicating the reason for failure.

2 Change the state of Precise Paging feature to OFF (W7M).ZW7M:FEA=1887:OFF;

Expected Outcome:The Precise Paging license is set to value “OFF”.

End

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Abbreviations

8 Abbreviations

0 – ZBCSU Base Station Controller Signaling Unit

BSC Base Station Controller

BSS Base Station Sub-system

BTS Base Transceiver Station

CCCH Common Control Channel

CI Cell Identity

CS Circuit-switched

IMSI International Mobile Subscriber Identity

LA Location Area

LAC Location Area Code

MS Mobile Station

MSC Mobile Switching Center

MC C Mobile Country Code

MNC Mobile Network Code

PCU Packet Control Unit

PoC Push to Talk over Cellular

RA Routing Area

RAC Routing Area Code

PS Packet Switched

SDCCH Stand-alone Dedicated Control Channel

SGSN Serving GPRS Support Node

SMS Short Message Service

TMSI Temporary Mobile Subscriber

TRX Transceiver

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