Patent ID: 8363645
Filing Date: 2013-01-29
Classification: H04L,H04M

Abstract:
1. A method for implementing call forwarding on user-determined user busy, applied in a call process of an Internet Protocol Multimedia Core Network Subsystem (IMS) centralized service, the method comprising the following steps of: step 1: establishing a call, by an IMS Circuit Switched Control Function (ICCF) on a called side, with a called terminal having IMS Centralized Service (ICS) capability after the ICCF receives a session request routed by a Call Session Control Function (CSCF) from a calling side, and then the called terminal ringing; step 2: sending, by the called terminal, a user-determined user busy message to the ICCF when a user of the called terminal rejects the call, wherein the called terminal uses Unstructured Supplementary Service Data (USSD) on a session control path in a circuit switched domain to send the user-determined user busy message to the ICCF; and step 3: notifying, by the ICCF, a Telecom Application Server (TAS) that the called terminal is in a user-determined user busy state through the CSCF, and the TAS initiating a procedure of call forwarding on user-determined user busy.