VISOR: VoIP Security Using Reputation

Voice over IP (VoIP) is an important step in communications. Along with the benefits of VoIP, such as high efficiency and low cost, come security challenges. Allowing access to the voice communication network over the Internet provides several new opportunities for attackers. This paper summarizes the security challenges and proposes VISOR, a VoIP security architecture. VISOR is a reputation system that monitors VoIP activity, analyzes the global traffic patterns, and distinguishes between wanted and unwanted participants. We describe the components of VISOR and provide an evaluation of its effectiveness.