以IP多媒體子系統為核心結合Presence服務的S-CSCF實作

Abstract

在3G/4G行動通訊的多媒體傳輸服務是架構於IMS (IP Multimedia Subsystem)之下，它提供了行動通訊用戶(Subscriber)許多創新的統合式多媒體服務。本論文中我們設計一個以SIP為主的集中式狀態伺服器(Presence Server)作為3G/4G網路上行動用戶與行動裝置的個人化、以及多媒體會談VoIP (Voice over IP)和IM (Instant Messaging)等狀態資訊呈現收集。而此Presence Server是同樣是以IMS中的S-CSCF和HSS架構為基礎，並以Open Source的SIP Server：SIP Express Router (SER)作為實作範本。透過本論文提出的集中式Presence Server能夠將3G/4G網路中各種網路資源與使用者資訊以Presence來呈現，並透過Presence的資訊改變來設定後續服務調適(Service Adaptation)，以建構出具情境式的3G/4G行動服務環境。

In 3G/4G mobile systems, IMS is the major core of multimedia communications, and it provides novel communication schemes for subscribers in converged networks. In the paper we design a centralized presence server, which follows the basic architectures of S-CSCF and HSS of IMS to design its functions and which implementation is based on the well-known open source: SER (SIP Express Router), to gather and represent personal information of subscribers, VoIP sessions, and Instant Messaging services in converged networks. By the way, every network resource and user situation can be represented by the presence service. The system can observe the changing of presence of network resources, device capabilities, and user behaviors to adapt the suitable communicating service and build a context-aware 3G/4G communicating environment.