Patent ID: 7983245

Claim:
A method of converting a session initiation protocol (SIP) message to a signaling system 7 (SS7) message comprising: at a communications node: (a) receiving a SIP INVITE request; (b) determining whether the SIP INVITE request is destined for a PSTN subscriber; (c) in response to determining that the INVITE request is destined for a PSTN subscriber: (i) determining whether the INVITE request contains subscriber content, wherein the subscriber content stored in the SIP INVITE request includes multimedia content; (ii) in response to determining that the INVITE request contains subscriber content, constructing, using the INVITE request, a PSTN-compatible SS7 message service message containing the subscriber content and forwarding the message service message to the PSTN subscriber, wherein the PSTN-compatible SS7 message service message comprises either a short message service (SMS) message or a multimedia service (MMS) message; (iii) constructing, using the INVITE request, an initial address message (IAM); and (iv) routing the IAM to a switching office associated with the PSTN subscriber.