nanog mailing list archives
Re: Can P2P applications learn to play fair on networks?
From: Marshall Eubanks <tme () multicasttech com>
Date: Thu, 25 Oct 2007 17:39:58 -0400
On Oct 25, 2007, at 1:09 PM, Sean Donelan wrote:
On Thu, 25 Oct 2007, Marshall Eubanks wrote:I have raised this issue with P2P promoters, and they all feel that thelimit will be about at the limit of what people can watch (i.e., fullrate video for whatever duration they want to watch such, at somewhere between 1 and 10 Mbps). From that regard, it's not too different from the limit _without_ P2P, whichis, after all, a transport mechanism, not a promotional one.Wrong direction.In the downstream the limit is how much they watch. The limit on how much they upload is how much everyone else in the world wants.With today's bottlenecks, the upstream utilization can easily be 3-10 times greater than the downstream. And that's with massively asymetric upstreams capacity limits.When you increase the upstream bandwith, it doesn't change the downstream demand. But the upstream demand continues to increase to consume the increased capacity. However big you make the upstream, the world-wide demand is always greater.
I don't follow this, on a statistical average. This is P2P, right ? So if I send you a piece of a file this will go out my door once, and in your door once, after a certain (& finite !) number of hops
(i.e., transmissions to and from other peers). So if usage is limited to each customer, isn't upstream and downstream demand also going to be limited, roughly tono more than the usage times the number of hops ? This may be large, but it won't be unlimited.
Regards Marshall
And that demand doesn't seem to be constrained by anything a human might watch, read, listen, etc.And despite the belief P2P is "local," very little of the traffic is local particularly in the upstream direction.But again, its not an issue with any particular protocol. Its how does a network manage any and all unbehaved protocols so all the users of the network, not just the few using one particular protocol, receive a fair share of the network resources?If 5% of the P2P users only used 5% of the network resources, I doubt any network engineer would care.
Current thread:
- Re: Can P2P applications learn to play fair on networks?, (continued)
- Re: Can P2P applications learn to play fair on networks? Joe Provo (Oct 23)
- Re: Can P2P applications learn to play fair on networks? Brandon Galbraith (Oct 23)
- Re: Can P2P applications learn to play fair on networks? James Blessing (Oct 23)
- Re: Can P2P applications learn to play fair on networks? Sean Donelan (Oct 23)
- Re: Can P2P applications learn to play fair on networks? Iljitsch van Beijnum (Oct 24)
- Re: Can P2P applications learn to play fair on networks? Sean Donelan (Oct 24)
- Re: Can P2P applications learn to play fair on networks? Sean Donelan (Oct 25)
- RE: Can P2P applications learn to play fair on networks? michael.dillon (Oct 25)
- Re: Can P2P applications learn to play fair on networks? Marshall Eubanks (Oct 25)
- Re: Can P2P applications learn to play fair on networks? Sean Donelan (Oct 25)
- Re: Can P2P applications learn to play fair on networks? Marshall Eubanks (Oct 25)
- Re: Can P2P applications learn to play fair on networks? Sean Donelan (Oct 25)
- Re: Can P2P applications learn to play fair on networks? Mikael Abrahamsson (Oct 25)
- Re: Can P2P applications learn to play fair on networks? Sam Stickland (Oct 26)
- RE: Can P2P applications learn to play fair on networks? Sean Donelan (Oct 25)
- Re: Can P2P applications learn to play fair on networks? Iljitsch van Beijnum (Oct 26)
- Re: Can P2P applications learn to play fair on networks? Geo. (Oct 26)
- Re: Can P2P applications learn to play fair on networks? Sean Donelan (Oct 26)
- Re: Can P2P applications learn to play fair on networks? Mikael Abrahamsson (Oct 26)
- Re: Can P2P applications learn to play fair on networks? Sean Donelan (Oct 26)
- Message not available
- Re: Can P2P applications learn to play fair on networks? Sean Donelan (Oct 27)