Availability analysis of an IMS-based VoIP network system

Abstract

In multimedia wireless networks, VoIP (voice over internet protocol) technology is commonly used to compress the voice information based on a various type of coding techniques, transform it to the packet data, and transmit with real time on IP network. Since the VoIP network is often faced by external threats, a number of security failures may occur at each level of end-user, server and service provider. In this paper we focus on an intrusion tolerant architecture combined an IMS (IP multimedia subsystem), which is a information management middleware developed by IBM Inc., with the VoIP network system. More specifically, we describe the stochastic behavior of the IMS-based VoIP network systems with/without intrusion tolerant mechanism by semi-Markov processes, and evaluate quantitatively their security effects and robustness in terms of both service availability and mean time to security failure. © 2010 Springer-Verlag Berlin Heidelberg.