Research Of IMS Client Platform Based On JSR281 Spec. And Its Implementation Of User Agent Tool

IMS(IP Multimedia Subsystem) is introduced by 3GPP(3rd Generation Partnership Project) in its Release 5 version,to support IP multimedia service.It is a whole new multimedia service,of which the core feature is to use SIP(Session Initiation Protocol). IMS can meet more fashionable and diversified multimedia service requirement of current customs.However,the majority of world's IMS networks are in experimental stage,and the development of IMS application is greatly limited.How to develop IMS client applications conveniently by utilizing IMS frame based on IETF,3GPP and JCP efficiently,is the main purpose pursued by application provider even 3G product developer.Early in 2006,JCP(Java Community Process) passed JSR281 Spec.to meet the requirement of application developers who are intend to develop corresponding application with IMS system.However,there are no products based on this specification on the market till now.The main task and innovations of this paper include these aspects as followed: First,after analyzing SIP and its application in IMS system,this paper makes up an IMS Client platform based on moto L J2.0 platform in connection with request to client by IMS system.It abstracts IMS under stratum technology and SIP protocol farthest to provides IMS API which comply with JSR281 fully,and makes the development of IMS Frame based applications convenient and fast.Then it designed and implemented an UA implementation based on JSR281.It is mainly made up of controlling module and service module.This paper introduced the implement of the two modules in detail.This UA implement has achieved basic service in IMS network such as meeting,immediate message and emerge.In the end,JSR281 IMS UA implement is tested in lab environment of Motorola.and it verifies the usability of JSR281 UA platform.Meanwhile,it demonstrates that JSR281 IMS client platform provides an efficient and convenient client developing plan through the implementation.