Narrowcasting: Implementation of Privacy Control in SIP Conferencing

In traditional conferencing systems, participants´ voices might by default be shared with all others. However a VOIP user might want to select a subset of session members to selectively exchange media streams. In this article, we describe an implementation of narrowcasting, a model for limiting such information streams in a multimedia conferences, as a class of policies, prototyping a system using existing standard Session Initiation Protocol (SIP) methods for controlling fine-grained narrowcasting sessions.