Evaluating the Security and Privacy Protection Level of IP Multimedia Subsystem Environments

In complex environments like the IP multimedia Subsystem (IMS), state of the art security solutions cannot always provide satisfactory protection against any type of attack. This paper addresses the security mechanisms utilized by IMS with respect to their susceptibility to SIP based attacks that have been described in the literature. This analysis also studies the effects of 3GPP´s security directions (i.e., IMS architectures) on limiting the attack chances. The protection mechanisms involved are evaluated considering three distinct and crucial factors: (i) whether the attacker is an insider or an external one, (ii) the time frame of the attack and (iii) how these attacks affect the messages´ confidentiality, authenticity and integrity as well as architecture´s availability and users´ privacy. A thorough review of the recently proposed protection frameworks is also provided together with an evaluation of the protection level they offer to the IMS architecture.