Voice service in evolved packet system

摘要

Methods and apparatus to manage voice service in evolved packet systems are disclosed. An example method in a User Equipment (UE) includes receiving a Non Access Stratum (NAS) protocol response message with a first indicator, the first indicator provided by lower layers of the UE to upper layers of the UE, responsive to the first indicator, initiating an IMS registration if the UE is not already registered with the IMS, and responsive to the UE having registered with the IP Multimedia (IM) Core Network (CN) Subsystem (IMS), determining availability of voice services over the IP Multimedia (IM) Core Network (CN) Subsystem (IMS).

主权项

1. A method in a User Equipment (UE), the method comprising:
receiving a Non Access Stratum (NAS) protocol Accept message with a first indicator indicating that an IMS voice over packet-switched session is supported, the first indicator being provided by lower layers of the UE to upper layers of the UE; responsive to the first indicator, performing an attempt to register with an Internet Protocol Multimedia Subsystem (IMS); and based on a failure of the attempt to register with the IMS, performing, by the UE, a combined tracking area update (TAU).