Connecting the worlds : multipoint videoconferencing integrating H.323 and IPv4, SIP and IPv6 with autonomous sender authentication

Abstract

In this paper we present a multipoint media conference software with extended network capabilities. Its core components combine an advanced, highly efficient H.264/AVC video coding system. Session signaling follows the SIP standard and simultaneously supports IPv4 and IPv6. Built upon an underlying peer-to-peer communication scheme, it further supports advanced integration with legacy MCUs and thereby enables hybrid sessions that extend into the H.323 world. We demonstrate how our software can span fully functional conferences across these worlds by deploying a passive gateway peer. Finally, we address security issues arising in distributed conferencing systems. It is shown, how the use of cryptographically generated identifiers enables the application to authenticate data on a packet level, thereby preventing abuse and impersonation of the conference overlay network.