초록 ▼

A distance learning system consists of a plurality of multi-cast clients of various classes and priorities with one multi-cast client as a primary multi-cast client, a multi-cast server, arbitrator and a distance learning session coordinator. The primary multi-cast client provides the default or pri

A distance learning system consists of a plurality of multi-cast clients of various classes and priorities with one multi-cast client as a primary multi-cast client, a multi-cast server, arbitrator and a distance learning session coordinator. The primary multi-cast client provides the default or primary Audio-Visual Material (AVM) stream. The Multi-Cast Server (MCS) setups a multi-cast over a point to multi-point connection which connects all multi-cast clients that are to take part in a particular distance learning session, along with the Primary multi-cast client. Additionally, the primary multi-cast client is connected to the MCS via a point-to-point link. The multi-cast clients and the primary multi-cast client receive an AVM material stream from the multi-cast server via the point to multi-point connection. When a multi-cast client wishes to speak, a speaking request is sent to the arbitrator, the arbitrator determines whether to grant or deny the speaking request. If permission is granted then a point-to-point link is established between the requesting multi-cast client and the MCS. The requesting multi-cast client then provides an AVM stream to the multi-cast server over the newly established point-to-point connection and the multi-cast server switches or provides the AVM stream associated with the requesting multi-cast Client over the point to multi-point connection. When the requesting multi-cast client is through speaking the MCS switches the AVM stream associated with the primary multi-cast client onto the point to multi-point connection and the point-to-point link with the requesting multi-cast client is terminated.

대표청구항 ▼

[ What is claimed:] [2.] A multi-cast server adapted for use in a video-conferencing system comprising:a means for setting up a point to multi-point connection between a multi-cast server and a plurality of clients, said point to multi-point connection capable of transmitting an AVM stream from the

[ What is claimed:] [2.] A multi-cast server adapted for use in a video-conferencing system comprising:a means for setting up a point to multi-point connection between a multi-cast server and a plurality of clients, said point to multi-point connection capable of transmitting an AVM stream from the multi-cast server to each of the plurality of clients;a means for receiving a default AVM stream;a means for dynamically accepting a point-to-point connection from any of the plurality of clients;a means for receiving an AVM stream originating from a client via a dynamically accepted point-to-point connection;a means for selecting either the default AVM stream or an AVM stream originating with one of the plurality of clients over the dynamically accepted point-to-point connection;a means for multi-casting a selected AVM stream over the point to multi-point connection wherein the source of the selected AVM stream is switched between the default AVM stream and one or more AVM streams received from a dynamic point-to-point connection; andan arbitrator for receiving speaking requests and granting speaking requests, wherein response to the arbitrator granting a speaking request, a point-to-point connection is dynamically established and the received AVM stream from the point-to-point connection is multi-cast as the selected AVM stream until the multi-cast server multi-casts the default AVM stream as the selected stream and terminates the point-to-point connection.