Audio Conferencing

Abstract

DefinitionAudio conferencing allows participants in a live session to hear each other.The audio is transmitted over the network between users, live and in real-time. Audio conferencing is one component of teleconferencing; the others are video conferencing, and data conferencing. Since the audio must be encoded, transmitted, and decoded in real-time, special compression and transmission techniques are typically used. In a teleconferencing system that is ITU-T H.323 [1] compliant, the G.711 [2] audio codec, which is basically uncompressed 8-bit PCM signal at 8 KHz in either A-Law or A-Law format, must be supported. This leads to bitrates of 56 or 64 Kbps, which are relatively high for audio but supported by today's networks.Support for other ITU-T audio recommendations and compression is optional, and its implementation specifics depend on the required speech quality, bit rate, computational power, and delay. Provisions for asymmetric operation of audio codecs have also been m ...