P2P agents for software distribution - saving the WAN from meltdown?!?
nanog at daork.net
Wed Jun 18 15:29:36 UTC 2008
On 19/06/2008, at 2:52 AM, Joe Abley wrote:
> On 18 Jun 2008, at 10:42, Adrian Chadd wrote:
>> <random type="idea from tonight">
>> If only there was a way for a SP to run a BitTorrent type service for
>> their clients, subscribing the BT server(s) to known-good (ie, not
>> torrents pre-seeded from trusted sources and then leaving it the hell
>> alone and not having to continuously dump specific torrent files into
> Automatically leeching and then seeding for long periods is trivial
> to set up if you can get an RSS feed with torrent enclosures. It is
> my (highly theoretical, naturally) understanding that many
> BitTorrent trackers make such feeds available.
> However just because you have a fast, on-net seed for particular
> torrents doesn't mean that your on-net leechers will necessarily
> pick it up. The behaviour I have observed with BitTorrent is that
> clients are handed a relatively short list of potential peers by the
> tracker, and it's quite common for sensible, close, local peers not
> to be included. My assumption has been that the set of potential
> peers passed to the client is assembled randomly.
> If this behaviour is widespread (i.e. if my observations are valid
> and my interpretation of those observations reasonable) then the
> more popular the content, the less likely leechers are to see the
> seed you want them to see. This relegates your local, on-net, fast
> seed to be a way of distributing unpopular content (that which is
> not being seeded by many other people).
> There has been at least one presentation at NANOG in the past couple
> of years which describes the benefit to ISPs of p2p, by virtue of
> keeping traffic for popular content on-net. From memory, however,
> that presentation was based on a non-deployed p2p protocol which
> made more of an effort to help peers find local peers than the
> clients I described above.
There was a product around that would keep track of torrents and fudge
the tracker responses to direct you to on-net peers where possible.
Not sure what it's called. Inline box thing, much like Sandvine,
Allot, etc. I imagine you could either inject the details of a local
seed you're running, or keep track of on-net users and inject those.
From a tracker software point of view, it would be fairly trivial to
weight peer lists to prefer peers within the same ASN I imagine.
Perhaps that could be turned in to same country, or what not. Better,
combine it with some kind of rough AS adjacency graph and <insert
algorithm here> and viola.
Is there any data available that would let that happen easily?
Obviously routing tables for the ASN/IP mapping, but what about rough
ASN adjacency? It doesn't really need to be updated that often - even
CAIDA's yearly data that they use to make their pretty pictures could
Seems like win/win/win - linux distribution vendors can pride
themselves on how much faster their torrents run, end users get better
speeds for their torrents, networks move less traffic off-net.
.. this is the part where someone bustles off and makes it go.
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