Home page logo

nanog logo nanog mailing list archives

RE: VoIP QOS best practices
From: "Stephen J. Wilcox" <steve () telecomplete co uk>
Date: Mon, 10 Feb 2003 19:01:39 +0000 (GMT)

On Mon, 10 Feb 2003, Ray Burkholder wrote:

QoS isn't necessarily about throwing packets away.  It is more like
making voice packets 'go to the head of the line'.  Of course, if you
have saturation, some packets will get dropped, but at least the voice
packets won't get dropped since they were prioritized higher.

Thats what I meant too...

To qualify further on where it needs to be deployed, its required on whatever 
the slowest link in the typical path to "the Internet". What I mean is that if 
you download your email you will utilise the whole bandwidth of the slowest link 
in the chain, this may be a dialup modem but more likely in the office to be 
your T1, you dont want this full utilisation of the link (which will occur in 
small bursts of a few seconds, dont forget with voice we are interested in per 
second traffic volumes not 5 minute averages!) to affect the jitter you need to 
implement priorities at this point.


Ray Burkholder

-----Original Message-----
From: Bill Woodcock [mailto:woody () pch net] 
Sent: February 10, 2003 14:05
To: Charles Youse
Cc: nanog () nanog org
Subject: RE: VoIP QOS best practices

    > That doesn't seem to make a lot of sense - is it that 
QoS doesn't work as advertised?

That's generally true as well.  But why would you need it?  What's the
advantage to be gained in using QoS to throw away packets, when the
packets don't need to be thrown away?

    > As someone who is looking to deploy VoIP in the near 
future this is of particular interest.

Go ahead and deploy it.  It's easy and works well.  It 
certainly doesn't
need anything like QoS to make it work.


  By Date           By Thread  

Current thread:
[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]