VoIP QOS best practices

Stephen J. Wilcox steve at telecomplete.co.uk
Mon Feb 10 17:56:13 UTC 2003


On Mon, 10 Feb 2003, Bill Woodcock wrote:

> 
>     > > Looking for some links to case studies or other documentation which
>     > > describe implementing VoIP between sites which do not have point to
>     > > point links.  From what I understand, you can't enforce end-to-end QoS
>     > > on a public network, nor over tunnels.  I'm wondering if my basic
>     > > understanding of this is flawed and in the case that it's not, how is
>     > > this dealt with if the ISPs of said sites don't have any QoS policies?
> 
> QoS is completely unnecessary for VoIP.  Doesn't appear to make a bit of
> difference.  Any relationship between the two is just FUD from people
> who've never used VoIP.

My conclusion too when I looked at this a couple years back. 

However, its important that the backbone is operating "properly" ie not
saturated which I think should be the case for all network operators, theres a
requirement tho if the customer has a relatively low bandwidth tail to the
network which is shared for different applications, its probably a good idea to
make sure the voip packets have higher priority than non-realtime data... (this 
last comment is a suggestion, I've not actually tested this in a real 
environment, low b/w lab tests tend to exclude other traffic flows)

Steve




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