# US 8,543,107 B1 · Method and system for delivering short message service (SMS) messages using the session initiation protocol (SIP) > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,543,107 B1 - Document ID: US8543107B1 - Status: Granted - Kind: B1 - Application number: 11/859,959 - Filed: 2007-09-24 - Granted: 2013-09-24 - Earliest claimed: 2007-09-24 - Assignees: Sprint Spectrum L.P. - Applicants: Lyle T. Bertz; William J. Routt; Ihab A. Guirguis; Ronald E. Lewis; Christopher R. Melus - Inventors: Lyle T. Bertz; William J. Routt; Ihab A. Guirguis; Ronald E. Lewis; Christopher R. Melus - Web page: https://patentgrep.com/patent/US8543107B1 ## CPC - H04W 4/14: Short messaging services, e.g. short message services [SMS] or unstructured supplementary service data [USSD] - H04L 51/066: Format adaptation, e.g. format conversion or compression - H04L 51/58: Message adaptation for wireless communication - H04L 61/4511: using domain name system [DNS] - H04L 61/4535: using an address exchange platform which sets up a session between two nodes, e.g. rendezvous servers, session initiation protocols [SIP] registrars or H.323 gatekeepers - H04L 61/4588: containing mobile subscriber information, e.g. home subscriber server [HSS] - H04L 65/1016: IP multimedia subsystem [IMS] - H04L 65/1033: Signalling gateways - H04L 65/1104: Session initiation protocol [SIP] - H04M 1/2535: {adapted for voice communication over an Internet Protocol [IP] network (Voice over Internet Protocol (VoIP) network equipment and services H04M7/006; implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP] H04L69/16)} - H04M 1/7243: with interactive means for internal management of messages - H04M 3/42068: {where the identifier is used to access a profile} - H04M 7/0045: {where the text-based messaging service is an instant messaging service} - H04M 15/8228: {Session based} - H04W 8/26: Network addressing or numbering for mobility support - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04M: TELEPHONIC COMMUNICATION (circuits for controlling other apparatus via a telephone cable and not involving telephone switching apparatus G08) ## Abstract 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. ## Claims ### Claim 1 A method for communicating with a mobile node via an Internet Protocol Multimedia Subsystem (IMS) network, said IMS network including an application server and a home subscriber server (HSS), said method comprising: said application server receiving a request to provide a communication service to said mobile node, said request including an identifier of said mobile node; in response to said request, said application server determining whether said mobile node is IMS registered; if said mobile node is IMS registered, said application server transmitting a packet-based protocol request to a call session control function (CSCF) serving said mobile node; and if said mobile node is not IMS registered, said application server querying an alternative registry to obtain a network address of said mobile node based on said identifier and transmitting an alternative packet-based protocol request to said network address. ### Claim 2 (depends on 1) The method of claim 1, wherein said application server functions as a short messaging service gateway (SMS-GW), and wherein said request to provide a communication service to said mobile node is a request to send an SMS message to said mobile node. ### Claim 3 (depends on 1) The method of claim 1, wherein said application server determining whether said mobile node is IMS registered comprises: said application server querying said HSS. ### Claim 4 (depends on 1) The method of claim 1, wherein said alternative registry is a domain name server (DNS). ### Claim 5 (depends on 1) The method of claim 1, wherein said packet-based protocol request and said alternative packet-based protocol request are Session Initiation Protocol (SIP) requests. ### Claim 6 A system comprising: a domain name server (DNS) storing Internet Protocol (IP) addresses of mobile nodes; an IP Multimedia Subsystem (IMS) network comprising a home subscriber server (HSS), an application server, and a call session control function (CSCF), said application server being configured to, in response to receiving a request to provide a communication service to a mobile node: (a) determine whether said mobile node is registered with said HSS; (b) if said mobile node is registered with said HSS, transmit a first-route SIP request to said CSCF; and (c) if said mobile node is not registered with said HSS, query said DNS to obtain an IP address of said mobile node and transmit a second-route SIP request to said IP address. ### Claim 7 (depends on 6) The system of claim 6, further comprising: a registration proxy for registering IP addresses of mobile nodes with said DNS.