Patent ID: 7636750

Claim:
A computing system for controlling scope of user participation during an ongoing real-time transport protocol (RTP) session in which a plurality of client stations communicate with each other through a central communication server, the system comprising: the central communication server for receiving from one of the plurality of client stations, during the ongoing RTP session, a single predefined control code requesting a change in scope of user participation in the session, for referencing a table to determine an appropriate response to the received single predefined control code, and for updating access control rules in accordance with the response, wherein the access control rules govern a state of participation of each of the plurality of client stations, thereby controlling the scope of participation for each user communicating therefrom, and wherein the central communication server allows and disallows bridging communications between one or more of the plurality of client stations based on the updated access control rules; and the plurality of client stations in the session having the state of participation responsively changed while retaining participation of at least one client station in the session, wherein an indication of the changed state of participation for each of the plurality of client stations is maintained thereon, thereby affecting which choices for changing the state of participation of others in the plurality of client stations are available and displayed to a user, which, when selected, provide a predefined control code to the central communication server, wherein the plurality of client stations have unique identifiers, wherein the unique identifiers are selected from a group consisting of an IP address, a telephone number, and a SIP address based on a type of link that ties each of the plurality of client stations to the central communications server, and wherein each and every of the plurality of client stations is configured to provide, during the ongoing RTP session, over a single server link connected to at least one of the plurality of client stations, the predefined control code and one or more of the unique identifiers of the plurality of client stations together in a payload block of a packet, concurrently with a packetized encoded signal comprising a sequence of packets representing an underlying voice communication.