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sizbut · October 25th, 2004, 01:50 PM

In Auto mode the IP Office tries to negotiate 729, then 723 and finally 711.

And that's a pretty good indication of the quality divided by bandwidth performance of each. Thinks G711 = CD, 729 = FM radio, 723 = AM radio - each on its days can be perfect but each is increasingly prone to potential probelms.

G729 gives better quality than G723 for not much bandwidth difference. For example on Ethernet 30Kbps versus 21Kbps (that may seems a big difference but not against full quality G711 at 86Kbps).

Over G723, G729 has better sound quality and a shorter conversion delay (40ms vs 80ms) which can be a factor since total latency becomes apparent to callers at 150ms.

October 25th, 2004, 01:50 PM	#3 (permalink)
sizbut PBXtech SILVER 25+ posts Join Date: Jun 2003 Posts: 95	Re: VoIP Compression Mode In Auto mode the IP Office tries to negotiate 729, then 723 and finally 711. And that's a pretty good indication of the quality divided by bandwidth performance of each. Thinks G711 = CD, 729 = FM radio, 723 = AM radio - each on its days can be perfect but each is increasingly prone to potential probelms. G729 gives better quality than G723 for not much bandwidth difference. For example on Ethernet 30Kbps versus 21Kbps (that may seems a big difference but not against full quality G711 at 86Kbps). Over G723, G729 has better sound quality and a shorter conversion delay (40ms vs 80ms) which can be a factor since total latency becomes apparent to callers at 150ms.