Depends upon the codec you are using. G.711 uses about 80 kbps in each direction, g.729 takes about 16 to 24 kpbs in each direction. So it is easy to do the math on how much capacity you need, and what your bandwidth budget is when you factor in traffic from other services. If you operate in a cisco world, they have info on their site for traffic engineering your outbound traffic. And if you have good relationship with your upstream provider, they could use the same rules to ensure traffic is regulated into your pipe. Ray Burkholder

-----Original Message----- From: Charles Youse [mailto:cyouse@register.com] Sent: February 10, 2003 14:22 To: Bill Woodcock Cc: nanog@nanog.org Subject: RE: VoIP QOS best practices

But I could conceivably have 10+ voice channels over a T-1, I still don't quite understand how, without prioritizing voice traffic, the quality won't degrade...

C.

-----Original Message----- From: Bill Woodcock [mailto:woody@pch.net] Sent: Monday, February 10, 2003 1:20 PM To: Charles Youse Cc: nanog@nanog.org Subject: RE: VoIP QOS best practices

> My main concern is that some of the sites that will be tied with > VoIP have only T-1 data connectivity, and I don't want a surge in > traffic to degrade the voice quality, or cause disconnections or > what-have-you. People are more accustomed to data networks going > down; voice networks going down will make people shout.

It works fine on 64k connections, okay on many 9600bps connections. T1 is way more than is necessary.

-Bill