boinc/html/bt

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Bittorrent file distribution system
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When several workunits require the same file (for instance any particularly big 
application file) it is really a waste to use a central server to distribute this
file. First of all a central server requires lots of bandwidth - which may be
quite expensive. Secondly getting 10'000 requests for the same multi-megabyte
file may be too much for even the largest of servers.

The solution is to harness the power of peer-to-peer computing in the domain of
volunteer and desktop grid computing by allowing the clients to share pieces of the
files they are downloading.

How it works
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Since noone can be trusted, "Bob" (a client) will need some way of knowing if "Eve" 
(another client) sent him a valid piece of the original file. To enable him to do
so Bob has downloaded a .torrent from the project servers. The .torrent describes
the file he is downloading; it contains hash values for each piece so that he can
check whether "Eve" is trying to cheat him.

If "Alice" also wants to download the same file as "Bob" they can each fetch a
different piece from the project servers and then share the pieces. Seen from
"Bob" and "Alice"'s perspective this potentially doubles the download rate (if you
see it from the project perspective it cuts the required network bandwidth in half).
As more people join the synergetic effect increases dramatically.

Isn't Bittorrent illegal?
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Bittorrent is a protocol for sharing files across the internet. As such it cannot
be illegal in itself - it is what you do with it that matters.
If you take a look at all the filesharing protocols out there Bittorrent seems to
be the one that has been taken into widespread use in the whitehat part of the 
internet. Several major companies, including the movie industry, have adopted the 
technology because of its unique ability to distribute load. To name a few uses:
- Bittorrent.com (Works with the movie industry, sells movies and shows)
- Blizzard Entertainment (Uses BT to distribute data patches for their World of
  Warcraft game)
- EletricSheep screensaver (Uses BT to distribute computed "dreams")

How do I enable this?
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Have a look at the INSTALL file located in the same directory as this file.