Internet Engineering Task Force (ietf) Requirements from Session Initiation Protocol (sip) Session Border Control (sbc) Deployments Requirements from Sip Sbc Deployments

This document describes functions implemented in Session Initiation Protocol (SIP) intermediaries known as Session Border Controllers (SBCs). The goal of this document is to describe the commonly provided functions of SBCs. A special focus is given to those practices that are viewed to be in conflict with SIP architectural principles. This document also explores the underlying requirements of network operators that have led to the use of these functions and practices in order to identify protocol requirements and determine whether those requirements are satisfied by existing specifications or additional standards work is required.