RTP media failover: problem statement
Nic Larkin, M. J. Taylor · 2016
Network-based functions that terminate large numbers of RTP media streams and that offer high availability, such as session border controllers or conference bridges, typically preserve the same IP address towards sources of RTP media across a failover event because it is impractical to signal a change of IP address towards large numbers of RTP sources sufficiently rapidly to keep media interruption intervals within acceptable limits. The need to preserve the IP address of RTP media terminating functions across a failover event imposes architectural requirements that can be difficult or costly to meet, particularly in network function virtualization environments. This document describes the problem, outlines the key requirements for a solution, and discusses the merits and shortcomings of various existing approaches to solving the problem, before arguing that a new solution is needed.