Patent ID: 8547969

Claim:
A method, implemented by a wireless transmit/receive unit (WTRU), for providing non-packet switched service in a target radio access technology (RAT) network, the method comprising: receiving a circuit switched (CS) service notification message including an explicit indication that indicates an identity the WTRU is to use after performing an inter-system change from a source RAT network to a target RAT network, wherein the explicit indication includes at least one bit which has a bit value of one that indicates an international mobile subscriber identity (IMSI) of the WTRU should be used after the inter-system change is performed and a bit value of zero that indicates that a temporary mobile subscriber identity (TMSI) allocated for the WTRU should be used after the inter-system change is performed; and transmitting a paging response message including an identity identified by the explicit indication after the inter-system change is performed.