Patent ID: 8358650

Claim:
A method for communicating calling name (CNAM) identification information associated with a session initiation protocol (SIP) originated call to a circuit switched network, the method comprising: at a SIP-SS7 gateway: receiving a SIP call setup message that includes a SIP calling subscriber identifier information; associating a telephone number with the SIP calling subscriber identifier information; generating an SS7 call setup message associated with the SIP call setup message, wherein the SS7 call setup message includes the telephone number; communicating the telephone number and SIP calling subscriber identifier information to a calling name interworking function (CIF) module; at the CIF module: storing the telephone number and the associated SIP calling subscriber identifier information in a local cache; receiving a CNAM query message containing the telephone number from a terminating switching office; transmitting a CNAM response message to the terminating switching office including SIP calling subscriber identifier information; and wherein storing the telephone number includes intercepting the SS7 call setup message at the CIF module, extracting the telephone number from the SS7 call setup message, and storing the telephone number with the SIP calling subscriber identifier information in the local cache.