Middleware for Secured Video-Conferencing

Video-conferencing over IP networks is rapidly becoming a popular application. Currently, there are two standards for signaling that are used in such applications. H.323 is the signaling standard from ITU-T (used by most commercial video-conferencing system) and SIP, which is an IETF approved standard for voice and video communications. In this paper, we present federated security mechanisms as developed within a large project (Vide.Net) on Internet2. We discuss an actual SIP client architecture. Issues and techniques for authentication and authorization in SIP and H.323 based systems are explained. Moreover, we provide insights towards building a federated authentication/authorization model for secured video-conferencing. This federated model utilizes emerging SAML technology that promotes single sign-on authentication and is a novel approach for inter-realm authentication. Call flows depicting behavior of secured video-conferencing are enumerated.