Methods and Apparatuses for Terminating an IP Multimedia Subsystem Service When IP Address is No Longer Allocated to the User

摘要

A method of terminating an IP Multimedia Subsystem enabled communication service involving a user terminal, the terminal having been allocated an IP address by an access network used by the terminal to access the communication service. The method comprises determining when the IP address is no longer allocated to the user by the access network, and as a consequence of the determination, terminating the IP Multimedia Subsystem communication service.