Can P2P applications learn to play fair on networks?

Tue Oct 23 13:59:52 UTC 2007

On Oct 23, 2007, at 9:07 AM, Iljitsch van Beijnum wrote:

>
> On 23-okt-2007, at 14:52, Marshall Eubanks wrote:
>
>> I also would like to see a UDP scavenger service, for those  
>> applications that generate lots of bits but
>> can tolerate fairly high packet losses without replacement. (VLBI,  
>> for example, can in principle live with 10% packet loss without  
>> much pain.)
>
> Note that this is slightly different from what I've been talking  
> about: if a user trips the traffic volume limit and is put in the  
> lower-than-normal traffic class, that user would still be using TCP  
> apps so very high packet loss rates would be problematic here.
>
> So I guess this makes three traffic classes.
>
>> In this case, I suspect that a "worst effort" TOS class would be  
>> honored across domains.
>
> If not always by choice.  :-)

Comcast has come out with a little more detail on what they were doing :

http://bits.blogs.nytimes.com/2007/10/22/comcast-were-delaying-not- 
blocking-bittorrent-traffic/

Speaking on background in a phone interview earlier today, a Comcast  
Internet executive admitted that reality was a little more complex.  
The company uses data management technologies to conserve bandwidth  
and allow customers to experience the Internet without delays. As  
part of that management process, he said, the company occasionally –  
but not always – delays some peer-to-peer file transfers that eat  
into Internet speeds for other users on the network.

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(My understanding is that this traffic shaping is only applied to P2P  
traffic transiting the Comcast network, not to
connections within that network.)

Regards
Marshall