Bearer independent call control (BICC) signaling front-end processor and implementation system and method for BICC ring back tone interactive voice response (IVR) service

The invention discloses a bearer independent call control (BICC) signaling front-end processor and an implementation system and method for BICC ring back tone interactive voice response (IVR) service, which are applied to a 3G R4 network based on a BICC protocol, wherein the BICC signaling front-end processor comprises a receiving module and a conversion module; the receiving module is used for receiving a BICC protocol message from a network element of a core network in the process that a subscriber initiates the ring back tone IVR service, and for receiving an internal interface protocol message from an application server (AS); and the conversion module is used for converting the BICC protocol message from the network element of the core network into the internal interface protocol message and transmitting to the AS, and converting the internal interface protocol message from the AS into the BICC protocol message and transmitting to the network element of the core network. In the invention, the AS and a media sever (MS) based on a session initialization protocol (SIP) protocol as well as the BICC signaling front-end processor are used on the 3G R4 network to realize the ring back tone IVR service.