IP Multimedia Subsystem (IMS) Security: A Review and Testbed Implementation

The IP Multimedia Subsystem (IMS) is the SIP functionality behind VoIP calls over a wireless network. IMS is a Global 3GPP standard that is required for wireless service providers to assure call persistence as a mobile user moves between networks within the service provider, and to support billing information and authentication as these same mobile users roam between service providers' networks. In this paper we review security mechanisms to support IMS signaling and media communication, and we examine practical limitations via a testbed implementation at Texas A&M University Internet2 Technology Evaluation Center (ITEC).