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Bittorrent Implements Cache Discovery Protocol

Posted by ryuzaki0 on from the middlemen-i-wouldn't-want-to-be dept.

An anonymous reader writes "CacheLogic and BitTorrent introduce an open-source Cache Discovery Protocol (CDP) that allows ISP's to cache and seed Bittorrent traffic. Currently, Bittorrent traffic is suffering from bandwidth throttling ISP's that claim that Bittorrent traffic is cluttering their pipes. This motivated the developers of the most popular Bittorrent clients implement protocol encryption to protect bittorrent users from being slowed down by their ISP's. However, Bram Cohen, the founder of Bittorrent doubted that encryption was the solution, and found (together with CacheLogic) a more ISP friendly alternative."

7 of 170 comments (clear)

  1. i wanna go fast by MrSquirrel · · Score: 5, Funny

    We have the technology -- we can make him stronger, faster, better! ...now, if only there were some more seeders.

    --
    A computer once beat me at chess, but it was no match for me at kick boxing.
  2. Off the cuff thought by Arimus · · Score: 5, Interesting

    Just read this and wonder what the legal position for ISP's will be with regards to caching non-legal P2P files (warez, music files etc)?

    With the files being on my PC and served from my PC I'm the responsible party... if the ISP then is caching that data to make it more available (speed/latency/load reduction etc) then the ISP could be deemed to being a party to an illegal act...

    --
    --- Users are like bacteria -> Each one causing a thousand tiny crises until the host finally gives up and dies.
    1. Re:Off the cuff thought by zhouray · · Score: 5, Informative

      I assumed you didn't read the article. It says "only for commercially licensed content".

    2. Re:Off the cuff thought by muftak · · Score: 5, Insightful

      On the cache the files are stored as file chunks, with only a reference to the file hash value, not the filename. So the ISP has no idea what is in the cache, so it is the same as the file being passed through their network.

    3. Re:Off the cuff thought by Andy+Dodd · · Score: 5, Interesting

      It looks like (from TFA), there will be restrictions in place that only allow caching of non-copyrighted, legal content.

      It goes a LONG way towards legitimizing BitTorrent in case anyone tries to sue Bram, but contains no real-world benefits.

      If ISPs want to reduce bandwidth overuse by seeders... Just IMPLEMENT MULTICAST ALREADY!

      Yes, I realize multicast has historically presented major problems in scalability at the backbone router level, but with modern processing power and memory economics, it shouldn't be that difficult to implement now, and in the end presents far more benefits (massive reduction in bandwidth usage) than its disadvantages (backbone routers need some pretty hefty amounts of memory to track all of the multicast groups.)

      Even "limited" multicast solutions like xcast (explicit multicast - basically instead of sending to a "multicast group" an IP datagram is given multiple destinations) would result in MASSIVE reductions in bandwidth usage by P2P applications like BitTorrent.

      Due to the nature of BitTorrent and how it is used in general, caching is just an extremely hackish and limited way of implementing a shitty form of multicast... If the backbone supported multicast, there wouldn't be any need for caching of torrents.

      --
      retrorocket.o not found, launch anyway?
    4. Re:Off the cuff thought by Sark666 · · Score: 5, Interesting

      When bittorrent 4.2 was released, there was already mention of this, and I thought ya right the isps will help with torrents, but supposedly isp caching (even copyright material) is allowed under the dmca.

      http://www.slyck.com/news.php?story=1231

      http://www4.law.cornell.edu/uscode/html/uscode17/u sc_sec_17_00000512----000-.html

      " If a file shows up on the network frequently, the cache stores that file so that its seeded in the network rather than by peers. ISPs appreciate this because their access networks are terribly congested with P2P traffic. Caches are legal and covered explicitly in the DMCA"

    5. Re:Off the cuff thought by mzs · · Score: 5, Insightful

      And who doles-out the multicast group addresses? I think the problem is harder than you think at first glance.