Patent ID: 7853697

Claim:
A method, comprising: detecting at a terminal device an end of a suspended network state; subscribing to registration state information of said terminal device in response to the detected end of said suspended network to cause a response to be generated, the response including information indicative of deregistration of previously registered user identities during the suspended network state; checking the response to said subscribing; and updating registration states of the user identities of a user of said terminal device based on the information given in said response; wherein based on the information given in said response: performing individual registration of at least one of the deregistered user identities when the response identifies that only some of the previously registered user identities have been deregistered during the suspended network state, and performing an initial registration procedure, including generating a register message comprising desired private and public identities, when the response includes information indicative that all previously registered user identities have been deregistered.