7 Mobility

23.0933GPPRelease 17Stage 2Technical realization of Completion of Calls to Busy Subscriber (CCBS)TS

The handling for CCBS specific mobility is described below.

7.1 Mobility during Activation

In order to allow the activation of CCBS when the call is released, the CC connection towards the MS shall be kept, to avoid any problems of mobility with the MS A.

Therefore the MSC shall maintain the CC connection with the MS A while T1 is running and until either T1 expires or the MSC sends a CCBS REQUEST ACK or CCBS REQUEST ERROR to the MS. After MSC has sent CCBS REQUEST ACK or CCBS REQUEST ERROR, the MSC A shall release the CC connection with MS.

7.2 Number used within CCBS Call

The activating MSC A shall store the originally dialled number in the Call Information container. The TranslatedBNo parameter shall contain destination B address stored in international E.164 format.

If the MS A is registered outside of the HPLMN during the initial call or when Remote_User_Free is received from the destination B network the HLR A may request the recall MSC A to change the number used for CCBS Call to the TranslatedBNo instead. Refer to the SDLs for originating MSC/VLR.

If CAMEL service was activated in the original call the HLR A shall not request to change the number used for the CCBS Call.

7.3 MS does Location Update

CCBS does place extra requirements for the Location Update procedure in the HLR when MS is monitored. Refer to clause 6.4.

7.4 Mobility during CCBS Call in the destination network

If MS registers to non-supporting network special handling has to be applied. Refer to clause 10.1.3.