This TS specifies the technical realization of the handling of calls originated by a UMTS or GSM mobile
subscriber and calls directed to a UMTS or GSM mobile subscriber, up to the point where the call is established.
Normal release of the call after establishment is also specified. Trunk Originated call is also modelled.
In the present document, the term MS is used to denote a UMTS UE or GSM MS, as appropriate.