电路交换域与IMS互通研究

IMS是3GPP组织在R5版本上提出的支持IP多媒体业务的子系统,它最显著的特点是采用了SIP协议。现在,UMTS系统中包含三个域:电路交换域,分组交换域和IMS。IMS必须和传统的电路交换用户如PSTN用户进行交互,这篇文章对电路交换域和IMS的互通作了探讨。文章首先简要介绍了IMS中用于互通的网络实体及其功能,然后分别从控制平面和用户平面描述了IMS用户和电路交换域用户的互通,最后给出了控制平面上的SIP协议和ISUP协议的映射。

Interworking of Circuit-switched and IMS

IMS has been added to Universal Mobile Telecommunication System core network since 3GPP Release 5, it is characterized by the use of SIP protocol. Now, UMTS network consists of the following three domains, Circuit-switched, Packet-switched and IMS. IMS need to connect to the old network like PSTN. This paper discusses the interworking of the Circuit-switch and IMS. This paper first gives a brief introduction of the entities that used for interworking of the Circuit-switch and IMS, then it describes the interworking of the two networks from the control panel and the user panel, finally the paper has a discussion of the mapping of the SIP and ISUP protocol.