A standard path towards scalable conferencing in the Internet

The work described in this Ph.D. thesis has been carried out within the context of computer networks and real-time multimedia applications over the Internet. Specifically, we focus on conferencing, a challenging service which experienced a wide growth during the last years. We examine the standardization efforts conducted in this field by the Internet Engineering Task Force (IETF), which are mainly focused on centralized conferencing as defined by the XCON Working Group. We actively contributed to such efforts by designing and implementing the defined framework and protocols, while also writing best current practice documents which are on the path to become Request For Comments (RFCs). The main outcome of such activities has been Meetecho, a standards-compliant multimedia conferencing and collaboration platform we developed. Meetecho has been conceived at the outset to be extensible towards a distributed architecture, yet being fully compliant with the XCON specification, in order to better fulfill scalability requirements resulting from its large-scale deployment. The distributed architecture, which is the subject of the DCON (Distributed Conferencing) proposal we submitted to the IETF, is thoroughly described herein, where we also provide the reader with the results of a scalability analysis we conducted in order to assess the actual performance improvement attainable with distribution. The figures obtained have been encouraging and definitely motivated us in pushing our proposal into the Internet standardization community. Finally, a remarkable part of this dissertation is focused on diagnosing and addressing issues that might arise when deploying multimedia architectures in the actual Internet.