Method and system for delivering short message service (SMS) messages using the session initiation protocol (SIP)

摘要

An Internet Protocol Multimedia Subsystem (IMS) network uses the Session Initiation Protocol (SIP) to provide communication services to mobile nodes. A short message service gateway (SMS-GW) in the IMS network receives a request to deliver a message to a mobile node. The SMS-GW determines whether the mobile node is IMS registered. If the mobile node is IMS registered, the SMS-GW may transmit a SIP MESSAGE request to a call session control function (CSCF) serving the mobile node in order to deliver the message to the mobile node. If the mobile node is SIP-capable but is not IMS registered, the SMS-GW may instead transmit a SIP MESSAGE request to the mobile node's IP address. To obtain the mobile node's IP address, the SMS-GW may query a domain name server (DNS) that stores associations between hostnames and IP addresses of mobile nodes.