5.2.10 Inter-MSC handover GSM to GSM in A/Gb-mode

23.1953GPPProvision of User Equipment Specific Behaviour Information (UESBI) to network entitiesRelease 5TS

In the Basic inter-MSC handover procedure (GSM to GSM) described in 3GPP TS 23.009 [5], UESBI-Iu shall be transferred from MSC-A to MSC-B. One reason for this is because UESBI-Iu may be needed in the case that there is a later handover from A/Gb mode to Iu mode under MSC-B.

The Inter-MSC Handover GSM to GSM is illustrated in FigureĀ 5.2.10-1 (copied from 3GPP TS 23.009 [5]).

Figure 5.2.10-1. GSM to GSM inter-MSC handover

Inter-MSC GSM to GSM handover is initiated as described in 3GPP TS 23.009 [5].

1 The UESBI-Iu is NOT sent by BSS-A to MSC-A.

2 MSC-A derives the UESBI-Iu from the IMEISV. The UESBI-Iu shall be sent by MSC-A to MSC-B in the MAP_Prepare_Handover request message.

If MSC-B did not receive the UESBI-Iu (for example because MSC-A does not support the PUESBINE Feature) then MSC-B shall ignore this fact.

3 MSC-B shall store the UESBI-Iu in case it is needed for a later A/Gb mode to Iu mode intra MSC-B handover.

The rest of the steps are as described in 3GPP TS 23.009 [5].

For Subsequent Inter-MSC handover, MSC-A shall transfer the UESBI-Iu to MSC-B’.