Voice over IP: Risks, Threats and Vulnerabilities

Voice over IP (VoIP) and Internet Multimedia Subsystem (IMS) technologies are rapidly being adopted by consumers, enterprises, governments and militaries. These technologies offer higher flexibility and more features than traditional telephony (PSTN) infrastructures, as well as the potential for lower cost through equipment consolidation and, for the consumer market, new business models. However, VoIP/IMS systems also represent a higher complexity in terms of architecture, protocols and implementation, with a corresponding increase in the potential for misuse. Here, we begin to examine the current state of affairs on VoIP/IMS security through a survey of known/disclosed security vulnerabilities in bug-tracking databases. This paper should serve as a starting point for understanding the threats and risks in a rapidly evolving set of technologies that are seeing increasing deployment and use. Our goal is to gain a better understanding of the security landscape with respect to VoIP/IMS, toward directing future research in this and other similar emerging technologies.