This post particularly describes the gateways in IMS which communication back and forth with a legacy endpoints.To get a overview of IMS itself click here and to get a detailed description of IMS and its architecture click here .
What is IM-SSF ?
IP Multimedia Service Switching Function is a gateway to provide IN service such s legacy VPN ( Virtual Private Network ).
What is R-IM-SSF ?
Reverse IP Multimedia Service Switching Function Works on reverse principle to connect IN network to IMS services using IMS services such as FMFM ( find me follow me ) .
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