19.1 Location management Procedures

09.023GPPMobile Application Part (MAP) specificationTS

For non-GPRS subscribers, this subclause comprises a number of processes to handle the mobile nature of the subscriber. The processes will be addressed by SCCP Sub-System Number (MSC, VLR or HLR) and the Application Context. The following processes are defined in this subclause:

Process Update Location Area:

Initiator: Update_Location_Area_MSC, subclause 19.1.1.2;

Responder: Update_Location_Area_VLR, subclause 19.1.1.3;

Process Update Location:

Initiator: Update_Location_Area_VLR, subclause 19.1.1.3, or

Update_Location_VLR, subclause 19.1.1.6;

Responder: Update_Location_HLR, subclause 19.1.1.4;

Process Send Identification:

Initiator: Update_Location_Area_VLR, subclause 19.1.1.3;

Responder: Send_Identification_VLR, subclause 19.1.1.5;

Process Subscriber Present HLR:

Initiator: Subscriber_Present_HLR, subclause 19.1.1.7;

Responder: Short_Message_Alert_IWMSC, subclause 23.4.3;

Process Cancel Location:

Initiator: Cancel_Location_HLR, subclause 19.1.2.2;

Responder: Cancel_Location_VLR, subclause 19.1.2.3;

Process Detach IMSI:

Initiator: Detach_IMSI_MSC, subclause 19.1.3.2;

Responder: Detach_IMSI_VLR, subclause 19.1.3.3.

Process Purge MS:

Initiator: Purge_MS_VLR, subclause 19.1.4.2;

Responder: Purge_MS_HLR, subclause 19.1.4.3.

As both the Update Location Area and the Detach IMSI processes use the same application context name, the MAP Provider cannot distinguish between them. Therefore, a Location Management Coordinator Process will act as one user for this application context. This process (one in MSC, one in VLR) will create the Update Location Area or the Detach IMSI process, depending on the first service primitive received in the respective dialogue.

Additionally, a Location Management Coordinator process in the HLR coordinates the two application processes "Update Location HLR" (subclause 19.1.1.4) and "RESTORE_DATA_HLR" (subclause 19.3.3) that are addressed by the same application context.

Location Management Coordinator MSC

On receipt of a request for location updating from the A-interface, the Location Management Coordinator in the MSC will:

– create the process Update_Location_Area_MSC in case the updating type indicated in the A-interface primitive indicates normal updating, periodic updating or IMSI Attach;

– create the process Detach_IMSI_MSC in case the updating type indicated in the A-interface primitive indicates IMSI Detach.

The respective primitive is then forwarded to the created process. Henceforth, the coordinator will relay all service primitives from provider to the user and vice versa, until a request or indication for dialogue termination is received. This last primitive will be relayed, too, before the Coordinator process returns to idle state.

Location Management Coordinator VLR

On receipt of a dialogue request for the Location Management Application Context (see Receive_Open_Ind macro in subclause 25.1), the Location_Management_Coordinator will:

– terminate the procedure in case of parameter problems or if the MSC indicated version Vr protocol; or

– continue as below, if the dialogue is accepted.

Depending on the first service primitive received from the MAP Provider in this dialogue, the user process is created:

– Update_Location_Area_VLR in case the primitive is a MAP_UPDATE_LOCATION_AREA indication;

– Detach_IMSI_VLR in case the primitive is a MAP_DETACH IMSI indication.

In case a MAP_U_ABORT, MAP_P_ABORT or a premature MAP_CLOSE indication is received instead, the process returns to idle state. If a MAP_NOTICE indication is received, the dialogue towards the MSC is aborted and the process returns to idle state.

After creation of the user process the service primitive received from the provider is passed to the user process. Henceforth, the coordinator will relay all service primitives from provider to the user and vice versa, until a request or indication for dialogue termination is received. This last primitive will be relayed, too, before the Coordinator process returns to idle state.

Location Management Coordinator HLR

On receipt of a dialogue request for the Location Management Application Context (see Receive_Open_Ind macro in subclause 25.1), the Location_Management_Coordinator will:

– terminate the process in case of parameter problems; or

– revert to MAP version Vr protocol if the VLR requests version Vr protocol; or

– continue as described in the following, if the dialogue is accepted.

The user process is created depending on the first service primitive received from the MAP service provider within this dialogue:

– Update_Location_HLR if the primitive is a MAP_UPDATE_LOCATION indication;

– RESTORE_DATA_HLR if the primitive is a MAP_RESTORE_DATA indication.

If a MAP_NOTICE indication is received instead, the dialogue towards the MSC is terminated and the process returns to idle state.

After creation of the user process the service primitive received from the MAP service-provider is passed to the user process. Henceforth, the coordinator will relay all service primitives from MAP service-provider to the MAP service-user and vice versa, until a request or indication for dialogue termination is received. This last primitive will be relayed, too, before the Coordinator process returns to idle state.

For GPRS subscribers, this subclause comprises a number of other processes to handle the mobile nature of the subscriber. The processes will be addressed by SCCP Sub-System Number (SGSN or HLR) and the Application Context. The following processes are defined in this subclause:

Process GPRS Update Location:

Initiator: GPRS_Update_Location_Area_VLR, subclause 19.1.1.3, or

SGSN_Update_HLR, subclause 19.1.1.8,

Responder: Update_GPRS_Location_HLR, subclause 19.1.1.4;

Process Cancel Location:

Initiator: Cancel_GPRS_Location_HLR, subclause 19.1.2.2;

Responder: Cancel_Location_SGSN, subclause 19.1.2.4;

Process Purge MS:

Initiator: Purge_MS_SGSN, subclause 19.1.4.4;

Responder: Purge_MS_HLR, subclause 19.1.4.3.

The following existing process is also used for GPRS subscribers :

Process Subscriber Present HLR:

Initiator: Subscriber_Present_HLR, subclause 19.1.1.7;

Responder: Short_Message_Alert_IWMSC, subclause 23.4.3;

Figure 19.1/1: Process Location_Management_Coordinator_MSC

Figure 19.1/2: Process Location_Management_Coordinator_VLR

Figure 19.1/3: Process Location_Management_Coordinator_HLR