Patent ID: 7068601

Claim:
A method for detecting congestion and automatically adjusting bandwidth of a codec in a packet network, comprising the steps of: establishing a session between end points in a network, each including a codec; processing session content to produce an encoded or compressed representation of that content; processing compressed representations of session content to produce replicas of original session content; negotiating a commonly-agreed to codec type between the codecs using a session control protocol; periodically generating “heartbeat” packets as control packets where absence of the heartbeat packets is an indication of network congestion; determining the absence of any packets in the session packet flow; incrementing an error counter when a missing packet is detected; determining whether or not to check the error counter against pre-defined thresholds after a selected time interval; comparing the current error count against a slowdown threshold; determining whether or not the codec is already operating at the lowest rate permitted, otherwise re-negotiating packet rate using H.323 protocol to select a lower bit rate codec to reduce network congestion, if and only if a current error count is smaller than a slowdown threshold value after the comparing step; and comparing the error count against a speedup threshold thus determining whether or not the codec is already operating at the highest bit rate permitted, otherwise re-negotiating the packet rate flow using H.323 protocol to select a higher bit rate codec corresponding to higher session quality, if and only if a current error count is smaller than a speedup threshold value.