13.6.3 Call Hold after Answer, LCLS not established

23.2843GPPLocal Call Local Switch (LCLS)Release 17Stage 2TS

13.6.3.1 Hold Request

When the UE makes a request for the hold function for the non-local call the MSC server shall signal LCLS-CONNECT_CONTROL message with LCLS-Connection-status-control set to "do not establish LCLS".

NOTE: this is to avoid the case that the party requesting hold (which is no longer intended to be connected to the held party) performs a handover into the same BSS and triggers local switching in the BSS.

13.6.3.2 Retrieval Request

When the UE makes a request to retrieve a held call the MSC server shall stop an announcement that was applied to the held party. The MSC shall request the MGW to re-establish communication to the held party by changing the through-connection of the bearer termination towards the served mobile subscriber to be both-way through-connected or by using the Join Bearer Termination Procedure.

If the call has been successfully negotiated for LCLS then MSC server shall signal LCLS-CONNECT_CONTROL message with LCLS-Connection-status-control set to "connect". If the BSS established local switching it shall notify the core network.