Initial Simulation Results That Analyze SIP Based VoIP Networks Under Overload

摘要

This paper presents the results of a simulation study that assessed SIP based VOIP networks under overload. This work addresses the issue of network level congestion controls in SIP based telephony networks. The simulation network consists of Media Gateways and Call Controllers, each with internal overload detection and control mechanisms. The simulation includes SIP timers tuned to operate gracefully with PSTN interfacing protocols. The traffic model is SIP based VoIP calls not involving application server or media server interactions. This work demonstrates that combining external overload controls with internal overload controls reduces blocking and increases goodput across the overload levels that ranged from 1 to 4 times the engineered load.