On 8 Jun 2012, at 09:47, "Kerry Milestone" <[email protected]> wrote:

> I have seen a transit provider who is/was preferring small packets 
> (traditional VoIP) but once the packets reached a larger size such as 
> containing the HD and extra frame rate components these were going down a 
> larger (layer 2, different framing etc) bandwidth channel with some extra 
> internal hops.  However it increased latency from the base layer such that 
> there was too much to actually be useful to build on the baselayer stream 
> presentation.  The only (ok.. easiest) fix in this case, was to move to a 
> different peer who actually wasn't treating VoIP with any difference.

i wonder if thats what really happened ? it seems incredible that packet size 
would dictate a preferred path.  more like the VoIP traffic being classified 
and the HD VoIP not being classified in the same way. where you able to test 
using a different application?

> Now for a telco to know/detect and oblige priority for particular streams 
> would be tricky.

now that's an understatement! but we do it with DPI for peer to peer and other 
traffic so it can be done. I would argue that it's an expensive solution - 
probably more than the cost of the bandwidth and certainly not with the margins 
on voice (!) and not something that in my view aligns with a net neutrality 
direction.

> 
> On 07/06/12 13:35, Matthew Ford wrote:
> >
> >    http://www.iab.org/cc-workshop/
> >
> > Mat
> 
> 
> 
> On 07/06/12 19:49, Neil J. McRae wrote:
>> in some cases yes - ATM based DSL lines are particularly bad at coping
>> with VoIP under congestion - I presented some stats from my days at COLT
>> on this at UKNOF4 I think.
>> 
>> However even with QoS and other priority chaos there is still no
>> guarantee even on IP friendly access links.
> 
> On 7 Jun 2012, at 13:12, Justin Finkelstein wrote:
> 
> > Good point - I hadn't thought of that. If we consider streaming video
> > (within the context of communications) we're then talking about 2-way
> > live video feeds. I imagine at this point, the bandwidth requirements
> > would jump rather considerably and the ability to shape/prioritise
> > this traffic would become more complex as (IIRC) we're not just
> > talking about small UDP packets any more.
> 
> 
> 
> 
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