IMS implementation

[hia...@yahoo.com]

Hello,

I will be part of a team that has been asked to build a framework for
IMS (IP Multimedia Subsystem). Are there any opensource options
available to me? Also, here are some key specifications that I have
identified. Am I missing anything?

ETSI ES 282 001: NGN Functional Architecture
ETSI ES 282 002: PSTN/ISDN Emulation Sub-system (PES); Functional
architecture
ETSI ES 282 003: Resource and Admission Control Sub-System (RACS):
Functional Architecture
ETSI ES 282 004: NGN Functional Architecture; Network Attachment Sub-
System (NASS)

ETSI ES 282 007: IP Multimedia Subsystem (IMS); Functional
architecture

ETSI TS 185 003: Customer Network Gateway (CNG) Architecture and
Reference Points
ETSI TS 185 006: Customer Devices architecture and Reference Points

ETSI TS 124 229: Internet Protocol (IP) multimedia call control
protocol based on Session Initiation Protocol (SIP) and Session
Description Protocol (SDP)

ETSI TS 182 012: IMS-based PSTN/ISDN Emulation Subsystem; Functional
architecture


Thanks,
Hilal