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Re: is this like a peering war somehow?
From: Michael.Dillon () btradianz com
Date: Fri, 20 Jan 2006 14:08:40 +0000

My guess would be that basically everybody doing triple play will 
prioritize the IPTV and VoIP packets in their network including the 
access. Considering that streaming UDP IPTV requires very very low 
loss, much better than Best Effort, this is needed to provide a good 
quality service.

This is preferential treatment for some packets and it makes perfect 
technological sense.

But it's no magic bullet. Streaming live media also requires low 
jitter, especially if you are selling it as TV because viewers
will join and leave channels often, as they change channels on
their remote controls. This means you can't have big local buffers
to hide jitter, therefore you have to build a network with enough
capacity so that packets are all cut-through switched.

It's possible to hide packet loss from IPTV by throwing away 
some other application's packets but you can't hide jitter 
on your network. And if you have built such a good network
that you don't have jitter, there is not going to be any
packet loss either so QoS does nothing at all.

Preferential treatment can degrade service, but it cannot
improve service. If you prefer an IPTV service then you are
degrading all other services. If a 3rd party measures the
true quality of your service without using IPTV, then they
will see a network with much worse performance than on a 
network which does not do preferential treatment.

No magic bullets.

And if you are spending the extra money to implement
preferential treatment, can you be sure that there is 
a market willing to pay extra for this?

--Michael Dillon

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