SS7 MAP/Lg+ to sip based call signaling conversion gateway for wireless VoIP

摘要

An SS7-based call protocol conversion gateway that translates between circuit-switched SS7 protocols and session initiation protocol (SIP) oriented protocol, allowing an E911 call initiated over a switched network to be routed by a VoIP network. The SS7-based call protocol conversion gateway provides a PSAP with MSAG quality (street address) information about a VoIP dual mode phone user without the need for a wireless carrier to invest in building out an entire VoIP core. Thus, wireless carriers may continue signaling the way they are today, i.e., using the J-STD-036 standard for CDMA and GSM in North America, yet see benefits of a VoIP network core, i.e., provision of MSAG quality location data to a PSAP.

主权项

1. A method of converting a call, passed over a switched telephone network, into a voice over Internet Protocol (VoIP) call, comprising:
receiving, at an intermediate call protocol conversion gateway, circuit-switched call signaling from a mobile switching center (MSC); converting, at said intermediate call protocol conversion gateway, said circuit-switched call signaling into session initiation protocol (SIP)-based call signaling; transmitting, from said intermediate call protocol conversion gateway, said SIP-based call signaling to a physical VoIP positioning center (VPC); receiving routing instruction back from said VoIP positioning center; and routing said received routing instruction back to said mobile switching center (MSC).