Patent ID: 8855104
Filing Date: 2014-10-07
Classification: H04L,H04W

Abstract:
1. A method for switching a session control path of an internet protocol multimedia core network subsystem centralized service, wherein, during an internet protocol multimedia core network subsystem centralized service session based on a first session control path, when a condition for switching the session control path is satisfied, the following steps are performed: A: one party of: party (a) an internet protocol multimedia core network subsystem centralized service user equipment and party (b) an internet protocol multimedia core network subsystem circuit switched control function corresponding to the internet protocol multimedia core network subsystem centralized service session transmits a request for switching the session control path to another party, wherein each of party (a) and party (b) can transmit the request for switching the session control path; B: after a receiving party of the request for switching the session control path receives the request, the receiving party identifies the internet protocol multimedia core network subsystem centralized service session corresponding to the request and sends a response of session control path switching acknowledgement to a transmitting party of the request; and C: said internet protocol multimedia core network subsystem circuit switched control function and said internet protocol multimedia core network subsystem centralized service user equipment sets the session control path corresponding to the identified internet protocol multimedia core network subsystem centralized service session as a second session control path, and subsequent session control information associated with the internet protocol multimedia core network subsystem centralized service session is transferred through the second session control path; wherein each of the first or second session control path is one of a packet switched session control path and a circuit switched session control path; and wherein the first and second session control paths are of different kinds of control paths; wherein said condition for switching the session control path is one or more of the following: (a) a domain interface corresponding to said first session control path does not meet communication requirement of the session control path or is not available, while a domain interface corresponding to the second session control path meets the communication requirement of the session control path; (b) according to service requirements, the session control path needs to be switched to the second session control path; (c) a message indicating to switch the session control path sent by the network according to operator's strategy is received; or (d) the session control path is switched to the second session control path based on internet protocol multimedia core network subsystem network management strategy, and wherein during the whole process of switching the session control path, a bearer control path and a bearer path of the session remain unchanged.