Measurement of SIP signaling performance for advanced multimedia services

The purpose of this paper is to provide an insight in the process of obtaining and interpreting values of the collection of metrics that are intended for performance evaluation of the Session Initiation Protocol (SIP). Three of the analyzed metrics are defined in a recently proposed Internet Engineering Task Force (IETF) draft, however, additional two metrics addressing negotiation and renegotiation procedures are introduced in this paper for the first time. The testing was performed upon emulated IP Multimedia Subsystem (IMS) network that incorporates a specialized network entity supporting dynamic quality of service (QoS) adaptation of SIP session parameters. Obtained results provided us with an overview of a typical behavior of SIP metrics' values. Furthermore, by comparing results obtained for different network scenarios, we were able to isolate several weaknesses of the testbed and deduce potential solutions to them.