VoIP QOS best practices

Mon Feb 10 18:34:55 UTC 2003

Yes, but most companies do not want to upgrade the access link to
unneeded levels just to ensure that VOIP never has contention. It is on
the access link where QOS matters, ingress and egress. That is where we
(AT&T) have deployed it and where it makes sense. It's not about pitting
one customer's traffic against another's across the core. The core is
over-provisioned for high bandwidth and simplicity. It is pitting one
customers applications against their other applications. It is about
large packets (1500 byte) vs. small VOIP packets. It is about getting
the VOIP out the door while less sensitive applications wait in queue if
that is what is required on the access link. It is usually about T1 and
below.

Michelle

Michelle Truman   CCIE # 8098
Principal Technical Consultant
AT&T Solutions Center
mailto:mtruman at att.com
VO: 651-998-0949 (NEW NUMBER)
w 612-376-5137 

-----Original Message-----
From: Valdis.Kletnieks at vt.edu [mailto:Valdis.Kletnieks at vt.edu]
Sent: Monday, February 10, 2003 12:23 PM
To: Charles Youse
Cc: Bill Woodcock; nanog at nanog.org
Subject: Re: VoIP QOS best practices 

On Mon, 10 Feb 2003 13:02:39 EST, Charles Youse <cyouse at register.com>
said:
> That doesn't seem to make a lot of sense - is it that QoS doesn't work
as advertised?

Qos is designed for dealing with "who gets preference when there's a
bandwidth
shortage".  Most places are having a bandwidth glut at the moment, so
the VoIP
traffic gets through just fine and QoS isn't able to provide much
measurable
improvement.