9.2 Terminating network processes

23.0873GPPRelease 17Stage 2TSUser-to-User Signalling (UUS) supplementary service

9.2.1 Procedures in GMSC

Figure 9.2.1.1 Procedure UUS_GMSC_Check_Forwarding.

This procedure is called when Resume Call Handling message is received from the remote MSC. If the message contains UUS related information, that is copied to the subsequent IAM message.

Figure 9.2.1.1: Procedure UUS_GMSC_Check_Forwarding

9.2.2 Procedures in MSC

Figure 9.2.2.1 Procedure UUS_ICH_Check_Support.

This procedure is called after Alerting/Connect message is received from B-subscriber. It checks whether UUS service is possible and if not whether the call setup can be continued.

Figure 9.2.2.2 Procedure UUS_ICH_Check_Forwarding.

This procedure is called when no reply is received from B-subscriber. It checks whether call forwarding is allowed from UUS service point of view.

Figure 9.2.2.3 Procedure UUS_ICH_Handle_LCF.

This procedure is used to add UUS information to Resume Call Handling message when Optimal Routeing late call forwarding is supported.

Figure 9.2.2.4 Procedure UUS_ICH_Set_Info_In_IAM.

This procedure is used to add UUS specific information to forwarded call IAM message.

Figure 9.2.2.5 Procedure UUS_ICH_UUS1_Implicit_Active.

This procedure is used to set UUS1 implicit service active at the remote MSC when only UUI for service 1 is received.

Figure 9.2.2.1: Procedure UUS_ICH_Check_Support

Figure 9.2.2.2: Procedure UUS_ICH_Check_Forwarding

Figure 9.2.2.3: Procedure UUS_ICH_Handle_LCF

Figure 9.2.2.4: Procedure UUS_ICH_Set_Info_In_IAM

Figure 9.2.2.5: Procedure UUS_ICH_UUS1_Implicit_Active