Design and experimental evaluation of an adaptive playout delay control mechanism for packetized audio for use over the Internet

We describe the design and the experimental evaluation of a playout delay c ontrol mechanism we have developed in order to support unicast, voice-based audio communications over the Internet. The proposed mechanism was designe d to dynamically adjust the talkspurt playout delays to the traffic conditi ons of the underlying network without assuming either the existence of an e xternal mechanism for maintaining an accurate clock synchronization between the sender and the receiver during the audio communication, or a specific distribution of the audio packet transmission delays. Performance figures d erived from several experiments are reported that illustrate the adequacy o f the proposed mechanism in dynamically adjusting the audio packet playout delay to the network traffic conditions while maintaining a small percentag e of packet loss.