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 …