Design And Implementation Of Presence And IM System Based On The CM-IMS

With the rapid development of Internet, as CM-IMS becomes greatly commercial,the research and application of Presence and Instant Messaging based on SIP areincreasing. Presence and Instant Messaging services provide presence information andmessaging communication in real time, so users can choose appropriate time andmanner to communicate with each other.This paper discusses the research background, meaning and development ofPresence and Instant Messaging services in CM-IMS network, summarizes thedefinition, position and profession ability of CM-IMS, analyzes the services models ofPresence and Instant Messaging and specifications related to SIMPLE, summarizes andcategorizes the functions which SIMPLE provides in combination with SIP eventframework and IMPP and specifies the relationship among the specifications, introducesthe significant protocol related to Presence and Instant Messaging services, designs thesignaling process of subscription, notification and publication, XML data format anddatabase format, implements the presence agent, resource list services and XCAP server,analyzes the technology related to MSRP relay and proposes an improved method formedia relay, sending AUTH via SIP proxy, implements the module of MSRP mediarelay and improves the implementation of MSRP relay server.On this basis, we set up the real network environment and verify the correctness ofimplementation.