9.4 Functional behaviour of GMSC

23.0793GPPRelease 17Support of Optimal Routeing (SOR)Technical realizationTS

When a call is being forwarded the forwarding leg is controlled by a process MT_CF_MSC which runs in the forwarding MSC (VMSC or GMSC). If CAMEL processing of the forwarding leg indicates that Basic Optimal Routeing of the forwarding leg should be attempted, the forwarding MSC may use the services of an associated GMSC for the forwarding leg, i.e. the associated GMSC requests routeing information from HLRC. In this case, the forwarding leg is processed in the same way as a mobile-originated call from mobile subscriber B.

The functional behaviour of a GMSC is specified in 3GPP TS 23.018 [6]. The procedures specific to Support of Optimal Routeing are specified in this clause.