Controlling Retransmission Rate for Mitigating SIP Overload
Recent server collapse in carrier networks (e.g., Skype outage) indicates that message retransmissions triggered by various SIP timers make the overload worse. The built-in overload control mechanism cannot handle overload conditions effectively. Since, the retransmissions stimulated by the overload introduce more overhead rather than reliability, the authors suggest mitigating the overload by reducing the retransmission rate. They propose a novel algorithm to detect the potential overload at the downstream servers and control message retransmission rate from upstream servers to mitigate the overload at the downstream servers.