8 Information storage

3GPP43.069Release 17Stage 2TSVoice Broadcast Service (VBS)

8.1 Information stored in the GCR

8.1.1 Information used for routing of service subscriber originated voice broadcast calls

Without a RANflex configuration, the GCR shall hold for a related MSC area for each group ID and cell from which voice broadcast calls can be established by service subscribers the broadcast call reference to be used for a voice broadcast call to be established and an indication whether the originating MSC is the group call anchor MSC.

In a RANflex configuration, the GCR shall hold for a related MSC area (i.e. for those location areas for which the related MSC is the group call serving MSC) for each group ID and cell (within those location areas for which the related MSC is the group call serving MSC) from which voice broadcast calls can be established by service subscribers the broadcast call reference to be used for a voice broadcast call to be established and an indication whether the group call serving MSC is the group call anchor MSC.

In a RANflex configuration with group call redundancy, the GCR shall hold for a related MSC area (i.e. for those location areas for which the related MSC belongs to the group call serving MSC redundancy pool) for each group ID and cell (within those location areas for which the related MSC can act as the group call serving MSC) from which voice group calls can be established by service subscribers the group call reference to be used for a voice group call to be established and an indication whether the group call serving MSC belongs to the group call anchor MSC redundancy pool.

If one of the following configurations applies:

a) without a RANflex configuration;

b) in a RANflex configuration, if the VMSC is the group call serving MSC; or

c) in a RANflex configuration with group call redundancy, if the VMSC belongs to the group call serving MSC redundancy pool:

If the VMSC is the group call anchor MSC or belongs to the group call anchor MSC redundancy pool, the GCR shall provide the broadcast call attributes related to that broadcast call reference as defined in subclause 8.1.2 and 8.1.3 to the VMSC and the VMSC shall establish the voice broadcast call.

If the VMSC is not the anchor MSC or does not belong to the group call anchor MSC redundancy pool, the GCR shall provide the broadcast call reference plus the routing information identifying the anchor MSC or anchor MSC redundancy pool to the VMSC and the VMSC shall route the voice broadcast call to the anchor MSC or anchor MSC redundancy pool.

If the following configuration applies:

d) In a RANflex configuration, if the VMSC is different from the group call serving MSC:

If the group call serving MSC is a relay MSC for the broadcast call, the GCR shall provide the broadcast call reference plus the routing information identifying the anchor MSC to the group call serving MSC which passes this information to the VMSC.

If the group call serving MSC is the anchor MSC for the broadcast call, the GCR shall provide the broadcast call reference to the group call serving MSC which adds the routing information identifying the anchor MSC (i.e. its own MSC address) and passes the information to the VMSC.

Then the VMSC shall route the voice broadcast call to the anchor MSC.

If the following configuration applies:

e) In a RANflex configuration with group call redundancy, if the VMSC does not belong to the group call serving MSC redundancy pool:

If the group call serving MSC redundancy pool is a group call relay MSC redundancy pool for the broadcast call, the GCR shall provide the group call reference plus the routing information identifying the anchor MSC redundancy pool to the requesting group call serving MSC which passes this information to the VMSC.

If the group call serving MSC redundancy pool is the group call anchor MSC redundancy pool for the broadcast call, the GCR shall provide the group call reference to the requesting group call serving MSC which adds the routing information identifying the anchor MSC redundancy pool and passes the information to the VMSC.

Then the VMSC shall route the voice broadcast call to the anchor MSC redundancy pool.

In a RANflex configuration with group call redundancy, the GCR shall provide the requesting MSC with "group call ongoing information". If the broadcast call is ongoing at another MSC within the redundancy pool, the requesting MSC shall forward the actual request to that MSC.

NOTE: In case the GCR function is distributed over different physical entities, each may hold only the information needed to treat requests coming from the MSCs connected to the physical GCR entity.

8.1.2 Static Broadcast call attributes

The GCR stores a list of static Broadcast Call Attributes for a given group call reference. These lists shall be programmed by the service provider at registration of the network specific service configuration. In RANflex configurations with group call redundancy these lists shall be identical in GCRs which are associated to MSCs belonging to the same redundancy pool.

The contents of each list related to requests of the group call anchor MSC is as follows:

– a list of cells inside the MSC area of the group call anchor MSC (in a RANflex configuration with or without group call redundancy, the cells belonging to a location area for which the group call anchor MSC is the group call serving MSC) into which the call is to be sent (part of the group call area), see subclause 8.1.2.1;

– a list of group call relay MSCs (or group call relay MSC redundancy pools) into which the call is to be sent;

– information on the cipher algorithm and the group key to be used for this voice broadcast call;

– information on the codecs allowed for this voice broadcast call. As an operator option, the EFR codec, standard half rate codec, AMR half rate codec, and AMR full rate codec can be supported;

NOTE: A pre-Rel-7 VBS capable mobile station will not be able to participate in a broadcast call using the EFR codec, AMR half rate codec or AMR full rate codec, if the mobile station is part of that group.

– a list of identities of dispatchers to which a dedicated link is to be established, see subclause 8.1.2.2;

– a list of identities of dispatchers which are allowed to initiate the voice broadcast call, see subclause 8.1.2.2;

– a list of identities of dispatchers which are allowed to terminate the voice broadcast call, see subclause 8.1.2.2;

– the default priority level related to that voice broadcast call if eMLPP applies, see subclause 8.1.2.3;

– an indication whether the uplink reply procedure is applicable for this voice broadcast call.

– in a RANflex configuration with group call redundancy: A list of GCR addresses identifying GCRs associated to MSCs within the redundancy pool.

The contents of each list related to requests of a group call relay MSC is as follows:

– a list of cells inside the MSC area of the group call relay MSC (in a RANflex configuration with or without group call redundancy, cells belonging to a location area for which the requesting MSC is the group call serving MSC) into which the call is to be sent (part of the group call area), see subclause 8.1.2.1;

– identity of the group call anchor MSC (or group call anchor MSC redundancy pool);

– in a RANflex configuration with group call redundancy: A list of GCR addresses identifying GCRs associated to MSCs within the redundancy pool.

8.1.2.1 Group call area

The group call area is defined as a list of cells. The cells shall be defined by their cell identification consisting of the Location Area Code and the Cell Identity as defined in 3GPP TS 48.008 and are therefore uniquely identified in the network.

In the case the group call area extends over several MSCs, only the cells belonging to the requesting MSC (in a RANflex configuration and in a RANflex configuration with group call redundancy, cells belonging to location areas for which the requesting MSC is the group call serving MSC) are included in the broadcast call attributes.

8.1.2.2 Dispatcher identities

Dispatcher identities shall be ISDN numbers or MSISDN numbers with the structure according to ITU‑T Recommendation E.164. They shall correspond both to the number to be used to establish a call toward the dispatcher and the number provided as calling line identification when the call is originated by a dispatcher.

The list of dispatcher identities to which a dedicated link is to be established shall be passed to the MSC so that the distribution function can be set up.

The list of dispatcher identities which are allowed to initiate voice broadcast calls is used by the anchor MSC for verification for a voice broadcast call establishment by a dispatcher.

The list of dispatcher identities which are allowed to terminate voice broadcast calls is used by the anchor MSC for verification for a voice broadcast call release by a dispatcher.

8.1.2.3 Priorities

If the eMLPP supplementary service is applied to a voice broadcast call, the priority level shall be stored in the GCR.

For further details see 3GPP TS 23.067.

8.1.3 Transient G roup Call Attributes

8.1.3.0 General

The GCR stores transient data for a given group call reference. These data are maintained by the GCR to reflect the current status of the corresponding voice broadcast call.

In a RANflex configuration with group call redundancy Transient GCR Data needs to be synchronized between all GCRs associated to MSCs belonging to the same redundancy pool.

8.1.3.1 Group Call Status Information

– a status flag indicating if a voice broadcast call with the related broadcast call reference is on-going, see subclause 11.3.1.1.1;

– in a RANflex configuration with group call redundancy: Address of the MSC within the redundancy pool, where the broadcast call is ongoing (if so).

8.1.3.2 Initial Talker Information

The relay MSC, and in a RANflex configuration (with or without group call redundancy) the group call serving MSC of the initiating service subscriber’s current LAC, if this MSC is different from the VMSC, interrogate the GCR twice when setting up the broadcast call: The first GCR interrogation is triggered in the relay MSC by the service subscriber or in a RANflex configuration (with or without group call redundancy) in the group call serving MSC by the MAP service SEND_GROUP_CALL_INFO received from the VMSC. The second GCR interrogation is triggered in the relay MSC by the MAP service Prepare Group Call or in a RANflex configuration (with or without group call redundancy), if the anchor MSC is the group call serving MSC, by receiving the IAM from the VMSC.

At the first GCR interrogation the GCR shall store transient data in the GCR which are retrieved with the second GCR interrogation. These data are:

– the initiating service subscriber’s IMSI;

– the originating cell id.

8.2 Information managed per subscriber

8.2.1 Stored in the HLR

The following additional information shall be stored in the HLR:

– the subscription option for voice broadcast calls which can be made in the HPLMN only or also in case of roaming;

– a list of all the group IDs for which a service subscriber has a subscription;

– an indication whether the subscriber is entitled to establish a voice broadcast call to one or more group IDs of his subscription.

The group IDs are defined in subclause 9.1.

A service subscriber shall not be provided with more than 50 group IDs.

8.2.2 Stored in the VLR

The list of all the group IDs a service subscriber is entitled to use and the entitlement to establish a voice broadcast call to a group ID shall be brought forward to a VLR at the same time as other subscriber information is copied, and VLR entries shall be modified when corresponding HLR records are changed.

8.2.3 Stored in the SIM

The information detailed in subclause 8.2.1 also needs to be stored on the SIM. The service subscriber shall be able to deactivate or reactivate a group ID by MMI interaction so that the mobile station ignores notification messages to this group ID, when the group ID is deactivated.

8.2.3a Stored in the USIM

The information detailed in subclause 8.2.1 also needs to be stored on the USIM. The service subscriber shall be able to deactivate or reactivate a group ID by MMI interaction so that the mobile station ignores notification messages to this group ID, when the group ID is deactivated.

For each group ID where data confidentiality may be applied, the USIM needs to store the cipher algorithm to be used and the possible group keys.

8.3 Information used for routing of dispatcher originated broadcast calls

Routing of dispatcher originated calls shall be performed on the MSISDN number received at a GMSC in the Initial_Address_Message.

– Because the group call reference is included in the called MSISDN number as defined in subclause 9.2d the routing information can be derived by the routing function of the GMSC. The GMSC afterwards directly routes the call request to the group call anchor MSC without requesting an HLR.