7.4 Purge MS Procedure

23.1193GPPGateway Location Register (GLR)Release 17Stage 2TS

This Purge MS procedure is used to cause the HLR to mark its data for an MS so that any request for routing information for a mobile terminated call, a mobile terminated short message or Network-requested PDP context activation will be treated as if the MS is not reachable. It is invoked when the subscriber record for the MS is to be deleted in the VLR or SGSN, either by MMI interaction or automatically, e.g. because the MS has been inactive for several days. This procedure is illustrated in figure 7.4/1. Each step is explained in the following list.

Figure 7.4/1: Purge MS procedure

Procedure:

1) The serving node, i.e., the VLR or the SGSN, sends a Purge MS message to the GLR.

2) When the GLR receives the Purge MS message from the serving node, it checks whether the subscriber is registered. If the subscriber is not registered, the GLR may report an error to the O&M interface, and sends back a negative response to the serving node. If the subscriber is registered, the GLR checks whether the purging notification came from the serving node where the MS was last registered.

– If the serving node that sent the purge MS request is the registered serving node, the GLR transports the received message to the HLR.

– If the serving node that sent the purge MS request is not the registered serving node, the GLR sends a purge MS ack to the serving node indicating that the TMSI or P-TMSI shall not be frozen.

3) When the GLR receives the response from the HLR, the GLR deletes the subscriber data and transports the received message to the serving node.

4) The serving node receives the Purge MS ack message indicating successful outcome of the procedure.

7.4.1 Functional requirements of GLR

7.4.1.1 Process Purge_MS_GLR

Figure 7.4/2 shows SDL chart for Process Purge_MS_GLR.

Figure 7.4/2(1): Process Purge_MS_GLR

Figure 7.4/2(2): Process Purge_MS_GLR