Jump to ContentJump to Main Navigation
Show Summary Details
Volume 35, Issue 2

Issues

Collapse Detection and Avoidance for SIP Architectures

Christoph Egger
  • Technische Universität Wien, Institute of Telecommunications, Wien, Austria
  • Université Europénne de Bretagne, Rennes, France
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Marco Happenhofer
  • Technische Universität Wien, Institute of Telecommunications, Wien, Austria
  • Université Europénne de Bretagne, Rennes, France
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Joachim Fabini
  • Technische Universität Wien, Institute of Telecommunications, Wien, Austria
  • Université Europénne de Bretagne, Rennes, France
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Peter Reichl
  • Technische Universität Wien, Institute of Telecommunications, Wien, Austria
  • Université Europénne de Bretagne, Rennes, France
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
Published Online: 2012-05-12 | DOI: https://doi.org/10.1515/pik-2012-0016

Abstract

The Session Initiation Protocol (SIP) relies on timer-based message retransmission for safeguarding reliable message transfer when deployed on top of the unreliable User Datagram Protocol (UDP) over IP. In this paper we present a detailed impact analysis of SIP timers onto the functionality of a system and its capabilities to recover from overload situations. The results of our event-based SIP simulations demonstrate that message retransmissions originating from a minor short-term overload can force a system into a deterministic congestion collapse when using default SIP timer settings. A recovery from this severe system overload situation is highly difficult or impossible, even if the system load is reduced substantially afterward. Our performance evaluation shows that an increase of timer T1's value significantly enhances the stability, robustness and the ability of systems to handle overload, whereas the resulting increase of response times is relatively small and overall system responsiveness can even improve in some cases. We propose an algorithm for implicit collapse detection as solution for dynamic timer T1 optimization. Based on monitoring of system load and pending transaction counts, our algorithm enables intermediate SIP proxies to detect congestion in a very early phase, allowing them to counteract in time, i.e., to modify timers and reject new system load in order to prevent the system from collapse.

Keywords.:

About the article

Published Online: 2012-05-12

Published in Print: 2012-05-04


Citation Information: PIK - Praxis der Informationsverarbeitung und Kommunikation, Volume 35, Issue 2, Pages 91–99, ISSN (Online) 1865-8342, ISSN (Print) 0930-5157, DOI: https://doi.org/10.1515/pik-2012-0016.

Export Citation

©2012 by Walter de Gruyter Berlin Boston.Get Permission

Comments (0)

Please log in or register to comment.
Log in