mirror of https://github.com/BOINC/boinc.git
43 lines
2.3 KiB
Plaintext
43 lines
2.3 KiB
Plaintext
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Bittorrent file distribution system
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When several workunits require the same file (for instance any particularly big
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application file) it is really a waste to use a central server to distribute this
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file. First of all a central server requires lots of bandwidth - which may be
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quite expensive. Secondly getting 10'000 requests for the same multi-megabyte
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file may be too much for even the largest of servers.
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The solution is to harness the power of peer-to-peer computing in the domain of
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volunteer and desktop grid computing by allowing the clients to share pieces of the
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files they are downloading.
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How it works
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Since noone can be trusted, "Bob" (a client) will need some way of knowing if "Eve"
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(another client) sent him a valid piece of the original file. To enable him to do
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so Bob has downloaded a .torrent from the project servers. The .torrent describes
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the file he is downloading; it contains hash values for each piece so that he can
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check whether "Eve" is trying to cheat him.
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If "Alice" also wants to download the same file as "Bob" they can each fetch a
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different piece from the project servers and then share the pieces. Seen from
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"Bob" and "Alice"'s perspective this potentially doubles the download rate (if you
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see it from the project perspective it cuts the required network bandwidth in half).
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As more people join the synergetic effect increases dramatically.
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Isn't Bittorrent illegal?
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-------------------------
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Bittorrent is a protocol for sharing files across the internet. As such it cannot
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be illegal in itself - it is what you do with it that matters.
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If you take a look at all the filesharing protocols out there Bittorrent seems to
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be the one that has been taken into widespread use in the whitehat part of the
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internet. Several major companies, including the movie industry, have adopted the
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technology because of its unique ability to distribute load. To name a few uses:
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- Bittorrent.com (Works with the movie industry, sells movies and shows)
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- Blizzard Entertainment (Uses BT to distribute data patches for their World of
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Warcraft game)
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- EletricSheep screensaver (Uses BT to distribute computed "dreams")
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How do I enable this?
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---------------------
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Have a look at the INSTALL file located in the same directory as this file.
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