> From: Enrico Marocco <[EMAIL PROTECTED]> > > This is actually a very interesting discussion, probably a perfect fit > for the IRTF P2P Research Group whose new charter (still under > refinement, AFAIK) will likely includes any research topics related to > P2P traffic localization.
indeed. We (Volker and myself with help from Aaron) are re-chartering the p2prg in order to include any topic/issue related to p2p networking. Anyone willing to contribute, please have a look at the wiki page: http://trac.tools.ietf.org/group/irtf/trac/wiki/PeerToPeerResearchGroup We tried to setup an "initial" list of topics we'd like to see addressed. Any question, suggestions, comment or flame, feel free to send it to Volker ([EMAIL PROTECTED]), myself or the list ([EMAIL PROTECTED]). Thanks. s. > I'd suggest to whoever is interested in this discussion to take a look > at the P2PRG page (http://irtf.org/charter?gtype=rg&group=p2prg) and > feel free to keep the conversation alive on the p2prg mailing list (now > Cc'ed). > > Enrico > > Maciej Wojciechowski wrote: >> Hi Arnaud, >> >> I think we both made our points clearly and I think we can both agree >> that we could continue this discussion infinitely. >> Since this group is not the right place to discuss particular >> scientific papers in details, I suggest we stop right now. >> >> Regards, >> Maciek Wojciechowski >> >> >> On Dec 4, 2008, at 6:44 PM, Arnaud Legout wrote: >> >>> Hi Maciej, >>> >>> Maciej Wojciechowski wrote: >>>> You are right, that a control experiment like yours can be very >>>> helpful in getting a better understanding of what is in fact going >>>> on. >>>> >>>> I'm talking about Marshall's sentence from first post in this >>>> thread "This would be a very encouraging reduction of inter-ISP >>>> traffic if it could be approached in practice by what we are doing >>>> here". I think that if those results could be reproduced it would >>>> be great. I'm just highly doubtful that they can. >>> We do not intend to overstate our results. We are simply performing >>> a study intended to >>> give a first answer to the three questions we present in the >>> introduction: >>> -How far can we push locality? >>> -What is, at the scale of a torrent, the reduction of traffic that >>> can be achieved with locality? >>> -Can locality significantly deteriorate the peers experience? >>> >>> I don't know what you mean by reproducibility. If you mean that we >>> will not find in the Internet >>> a torrent with the exact same characteristics than the ones we have >>> evaluated, you are right. >>> However, our results show that we can push locality further than >>> what was done up to now >>> with a great reduction on the inter-ISP traffic. Claiming that this >>> reduction will be 2 orders of magnitude >>> on a real torrent, or 1.75 or whatever you want would be pointless. >>> It will be much better >>> than what you can obtain with the locality values considered up to >>> now (around 80%), without a >>> negative impact on peers download completion time. This is the >>> important >>> point. >>> >>> >>>> like? Why is it 20kB/s and not 200kB/s or 1037kB/s? Why 100MB and >>>> not 257MB or 2057MB? I have never heard of inter ISP link with >>>> 2000kB/s capacity (not mentioning the 40kB/s). I have heard about >>>> 10Gbit/s ones though. I cannot see them anywhere in your work... >>>> >>>> Few things that in my opinion are significant and are not taken >>>> into consideration: >>>> - other web activities (like web browsing, gaming, ftp, >>>> youtube,...) of the users >>>> - setting arbitrary max download and max upload speeds >>>> - downloading many torrents at the same time >>>> - vast part of real-world users are hidden behind a NAT >>>> - users with very big symmetric links (e.g. 100Mbit) that are >>>> seeding much more than downloading. Yes, there are such users... >>>> - and many, many more. >>>> >>>> Honestly, there are hundreds of factors, many of them very complex. >>>> Do you really want to argue that the simplified model you presented >>>> is good enough to reason about bittorent behavior? >>> This is exactly the point. There are so many factors that you cannot >>> test everything. >>> Either you measure real torrents and traffic, but it is only >>> relevant for what you have measured at that moment, >>> and you will never understand this way the impact of some specific >>> parameters. We did that for BT in another >>> context (see our IMC'2006 study) >>> and know that this is just one part of the big picture that allows >>> you to understand what is going on. >>> >>> Or, you make controlled experiments varying one parameter at a time. >>> The question here is how you chose the >>> fixed parameters and the range of what you vary. This is based on >>> experience and understanding you got from >>> in the wild experiments, and related work. >>> We are quite confident that our choices are relevant and allow us to >>> show what we wanted to show. >>> But of course it is always possible to make different choices and to >>> compare different approaches. >>> This is why research is great. >>> >>>> I want one thing to be clear: I really like your paper, as a study >>>> work that can help us understand the problem better. But with all >>>> due respect, I simply cannot agree that this is a valid bittorrent >>>> model. Hence, I don't see why those results would give us knowledge >>>> about how the deployed ALTO system would perform in the real-world. >>> All depends on what you mean by knowledge. Don't attribute to our >>> study a larger scope than what we described. >>> Our study simply says that if you increase the locality up to very >>> high values >>> then the inter-ISP traffic will be lower without negative impact on >>> end-users. >>> Forget about absolute values, they are only there to compare >>> different experiments in the context of our study. >>> If you claim that we haven't shown that it makes sense to consider >>> high locality values, then I have to disagree. >>> >>> Regards, >>> Arnaud. >> >> _______________________________________________ >> alto mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/alto > > _______________________________________________ > alto mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/alto _______________________________________________ alto mailing list [email protected] https://www.ietf.org/mailman/listinfo/alto
