Gautam Nair

US Patent:

20020126626, Sep 12, 2002

Filed:

Feb 28, 2002

Appl. No.:

10/085837

Inventors:

Kundan Singh - New York NY, US
Gautam Nair - New York NY, US
Henning Schulzrinne - New York NY, US

Assignee:

THE TRUSTEES OF COLUMBIA UNIVERSITY IN THE CITY OF NEW YORK - New York NY

International Classification:

H04J003/16

US Classification:

370/260000, 370/465000

Abstract:

A conferencing server is provided for a data network telephony system for facilitating multi-party call conferencing. The conferencing server generally includes a session initiation protocol (SIP) signaling interface and a media conferencing module. The media conferencing module includes a number of selectable media decoders compliant with known media CODEC protocols, such as G.711. A number of media stream queues s are selectively coupled to the media decoders for storing the decoded incoming media streams. A jitter correction processor is provided to compensate for arrival time jitter in the data stored in the media stream queues. A mixer, which receives the jitter corrected data from each of the queues, generates an aggregate conferencing stream of all active participants and generates individual participant conference streams for each active participant in the conference. A number of selectable media encoders are then used to encode the individual participant conference streams in accordance with a media CODEC protocol supported by the respective participant. The encoded participant conference streams are then distributed to the various conference participants via the data network, such as the Internet.