Implementing Bittorrent Protocol

Question

I am looking for a tutorial/blog post on how to implement bittorrent protocol step by step. How it works? How do you make requests to peers? and talk to trackers.

I do not mind the programming language (java,ruby,perl,c#)

I am interested in this and feel there has got to be some better knowledge out there so I put a bounty up. I'm looking for tutorials / walkthroughs of the protocol but any starting out pointers would be nice to see too. — lsl, Sep 05 '11 at 12:10

score 28 · Answer 1 · answered Jul 30 '11 at 17:27

28

the complete description of bittorrent protocol:

http://jonas.nitro.dk/bittorrent/bittorrent-rfc.html

answered Jul 30 '11 at 17:27

pesarak

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jonas.nitro.dk/bittorrent/bittorrent-rfc.html is a terrible source about the BitTorrent protocol. Parts of it is very convoluted and other parts is outright wrong. A better source is the inofficial specification here: https://wiki.theory.org/BitTorrentSpecification or the official here: http://bittorrent.org/beps/bep_0003.html – Encombe Oct 16 '16 at 19:34
The link you provided is no longer accessible, which renders the whole answer useless now. Would you like to update it? perhaps adding some short details into the post itself? – Viacheslav Shalamov Jan 08 '23 at 17:04

score 24 · Answer 2 · answered Jun 13 '09 at 13:41

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There is the libtorrent library.

Here's the API documentation and examples.

answered Jun 13 '09 at 13:41

Jonathan Prior

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score 11 · Answer 3 · answered Apr 24 '14 at 03:29

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This is good source http://www.kristenwidman.com/blog/how-to-write-a-bittorrent-client-part-1/ She explains the process step by step...

answered Apr 24 '14 at 03:29

Bhushan Lodha

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score 9 · Answer 4 · edited Sep 05 '11 at 12:50

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I'd suggest you look at the spec and sources of some OSS clients. You'll have to do some work, but that's how programming works.

edited Sep 05 '11 at 12:50

sanmai

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answered Jun 13 '09 at 13:47

Armandas

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score 8 · Answer 5 · answered Jun 13 '09 at 14:08

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I'm currently implementing a BitTorrent client in Java using this specification.

answered Jun 13 '09 at 14:08

macbirdie

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Have you completed the implementation? If so, is it open source? – S. Sandeep Apr 17 '20 at 11:46

goododd · Answer 6 · 2012-07-26T17:24:31.797

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Implementing the protocol is not that hard by following the specs. However, there are lots of internal things like storage, scalable server, peer/piece pick algorithm, etc.

Earlier BitTorrent implementation or BitTornado used python, which is easy to read. I personally found them useful to understand the internals.

edited Jul 26 '12 at 17:24

answered Jul 23 '12 at 23:47

goododd

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score 4 · Answer 7 · edited May 08 '22 at 08:10

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Qt is very easy to read so you can read the Qt Torrent Example (C++)

edited May 08 '22 at 08:10

Daniel

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answered Sep 10 '11 at 20:15

Derick Schoonbee

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score 3 · Answer 8 · answered Sep 05 '11 at 12:21

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This is a implementation of the bittorrent protocol done in .NET. Its source code is available on github and it has documentation

Monotorrent

answered Sep 05 '11 at 12:21

blessanm86

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Implementing Bittorrent Protocol

8 Answers8

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