Abstract

The session initiation protocol (SIP) is rapidly being adopted as the signaling protocol for establishing, modifying and terminating multimedia sessions. With the increasing use of SIP in large deployments, it is now becoming apparent that the current SIP design does not easily scale up to large network sizes and SIP servers are not well equipped to handle overload conditions. When a SIP server is operating close to or above its capacity limit, message retransmissions by various SIP timers can cause the network to be severely overloaded and result in an extremely low goodput. In this paper, we first provide a detailed analysis of the behavior of SIP servers under overload. We show that SIP servers are often unable to recover from congestion collapse once it has occurred and that overload can spread throughout a network of SIP servers. We then discuss mechanisms and algorithms for controlling overload in these servers. We found that performing overload control locally at a server provides a simple remedy for light cases of overload; however, it is ineffective in handling higher amounts of load. Finally, we investigate distributed overload control mechanisms for SIP and show that they are effective in controlling overload of SIP servers.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.