|Publication Date:||1 February 2007|
The IP Multimedia Subsystem (IMS) as specified by 3GPP has been adopted for use to support session and other Session Initiation Protocol (SIP) based services in the Next Generation Networks (NGN). This document describes the overall ATIS NGN functional architecture based on the IMS architecture, its subsystems, and the relationships between them. It defines Functional Entities (FEs), identifies reference points, and provides relationships with other industry NGN architectures.
The functional architecture provided in this TR allows a clear
distinction between definition/specifica
Although this document is targeted primarily at an NGN architecture, it is clear that the accommodation of legacy Public Switched Telephone Network/Integrated Services Digital Network (PSTN/ISDN) terminals and/or interworking with the PSTN/ISDN is an important consideration with respect to the NGN deployment.
The specific protocols used within the NGN are defined in relevant signaling-related or managementrelated documents and are not specified in this document.