Design and Implementation of an Open Source IMS Enabled Conferencing Architecture

摘要

In this paper we embrace an engineering approach to service delivery over the Internet, by presenting an actual implementation of a conferencing framework compliant with the IP Multimedia Core Network Subsystem (IMS) specification. The architecture we describe has been conceived at the outset by taking into account ongoing standardization efforts inside the various active international bodies. At its current state, it is capable to provide video conferencing facilities with session management capabilities and floor control. The system presented is intended to serve as a running experimental testbed useful for protocol testing, as well as field trials and experimentations. It will be first described from a high level design perspective and subsequently analyzed in further detail by highlighting the most notable implementation choices. A mapping between the actual system components and the corresponding IMS logical functions will be provided and a discussion concerning those parts of the system which somehow depart from the IMS paradigm will be conducted. This on one hand will help the reader figure out potential discrepancies between our solution and the IMS model; on the other hand will open space for discussion around some important open issues on which the international research community still has to attain a rough consensus.