Re: [p2prg] New version of the mythbuster-ing draft

Enrico Marocco <enrico.marocco@telecomitalia.it> Fri, 21 August 2009 07:50 UTC

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Date: Fri, 21 Aug 2009 09:51:14 +0200
From: Enrico Marocco <enrico.marocco@telecomitalia.it>
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Subject: Re: [p2prg] New version of the mythbuster-ing draft
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Stevens.Le_Blond@sophia.inria.fr wrote:
> The savings will indeed have something to do with "the number of peers per
> AS" but this can be refined.
> 
> To save cross-domain traffic "globally," you need 1) domains to be big
> enough so you will have more than one *simultaneous* peer for big torrents
> and that 2) the number of big torrents per domain to outweight the number
> of small torrents. Even if it's possible to save a lot for big torrents,
> that doesn't mean you can save for most torrents, especially because there
> are more small torrents than big ones. Fortunately though, big torrents
> also generate much more cross-domain traffic than small ones.
> 
> As I said during my talk at the last IRTF session, we have found that the
> top 1,000 torrents on the 214,443 torrents that we have crawled generated
> about half of the "global" cross-domain traffic.
> 
> Let me know if this answers your question or if you want me to elaborate
> more about this topic. You can also refer the Section 6.3 of our paper
> [LeBlond] for more info.

Well, this is certainly a useful perspective. What we need now is some
text to reflect it in section 3.1.2; if you want to propose some, that
will be more than welcome. Otherwise we'll figure something out and will
reiterate the discussion on the next version of the document.

>> How about replacing the above with the following text?
>>
>> 4.  Experiments with real BitTorrent clients run by researchers a INRIA
>>     [LeBlond] have shown a 40% reduction in cross-domain traffic on a
>>     global scale, with local peaks up to the 99.5% in exceptionally
>>     favorable conditions.
>>
> 
> That's better but I would add some numbers to make it clear that "global
> scale" actually means at the scale of the Internet. "Global" scale could
> be interpreted as all torrents (resp. a single torrent) but from the point
> of view of a single AS. Something like this:
> 
> 4. Experiments with real BitTorrent clients and real distributions of peers
>    per AS run by researchers at INRIA [LeBlond] have shown that ASes
>    with 100 peers or more can save 99.5% of cross-domain traffic
>    with high values of locality.
> 
>    They have also shown that at a global scale, i.e., 214,443 torrents,
>    6,1113,224 unique peers, and 9,605 ASes, high locality can save 40% of
>    global inter-AS traffic , i.e., 4.56 Petabytes (PB) on 11.6 PB. This
>    result shows that locality would be beneficial at the scale of the
>    Internet.

Perfect, thanks!

-- 
Ciao,
Enrico

Attachment: smime.p7s

[p2prg] New version of the mythbuster-ing draft Enrico Marocco
Re: [p2prg] New version of the mythbuster-ing dra… Stevens.Le_Blond
Re: [p2prg] New version of the mythbuster-ing dra… Fabio Hecht
Re: [p2prg] New version of the mythbuster-ing dra… Enrico Marocco
Re: [p2prg] New version of the mythbuster-ing dra… Enrico Marocco
Re: [p2prg] New version of the mythbuster-ing dra… Stevens.Le_Blond
Re: [p2prg] New version of the mythbuster-ing dra… Enrico Marocco
Re: [p2prg] New version of the mythbuster-ing dra… Fabio Hecht

Re: [p2prg] New version of the mythbuster-ing draft

Attachment: smime.p7s