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Could someone explain what this is?
by quchen 13y ago
Could someone explain what this is?
- nutmeg 13y agoThe Bittorrent tracker software used to run What.CD, a popular music torrent site.
- aroch 13y ago'Gazelle' is the bittorrent tracker frontend developed by What.CD (For those not in the know, one of the largest music trackers out there).
- bigdubs 13y agoactually 'ocelot' is the tracker itself, gazelle is just the site that the users access to get the torrents
- aroch 13y agoI corrected myself as soon as I posted...Not enough coffee this morning
- quchen 13y agoAh, thanks.
- andrewflnr 13y agoSo, what is a bittorrent tracker?
- dewey 13y agohttp://en.wikipedia.org/wiki/BitTorrent_tracker http://en.wikipedia.org/wiki/BitTorrent_tracker
- FZeroX 13y agoThe tracker tells you who else has the files you want, in a nutshell. Basic bittorrent outline: You download a .torrent file which contains (amongst other things) a list of files, their hashes, and a list of trackers to connect to. Your BitTorrent client connects to the tracker and says "Hi, who else has or is looking for these files"? It returns a list of these people (aka "peers") and your BitTorrent client then connects directly to peers to download the files (and upload them to other people).
- andrewflnr 13y agoAnd all this time I thought a torrent file had the actual peers in it. So you don't even really need the .torrent if you have the addresses of some trackers that know where the files are that you want?
- nadaviv 13y agoYou would also need the torrent's hash (which enable you to specify to the tracker which files you want exactly). That's how magnet link [1] works - they contain the torrent's hash and optionally a list of trackers (most clients today support DHT [2], a decentralized tracker-less way to find peers). [1] https://en.wikipedia.org/wiki/Magnet_URI_scheme https://en.wikipedia.org/wiki/Magnet_URI_scheme [2] https://en.wikipedia.org/wiki/Distributed_hash_table https://en.wikipedia.org/wiki/Distributed_hash_table
- FZeroX 13y agoI made a few simplifications for brevity and "these files" was one of them. What the .torrent actually contains is a list of the files and how those files are divided up into chunks of equal size (say half a megabyte per chunk). The bulk of the torrent is a list of hashes of each chunk, which allows your client to verify the data it has received from other peers. If you then take a hash of <<the part of the torrent that lists the files and the chunk hashes>> the resulting hash is known as the infohash. The infohash describes this particular torrent uniquely, and it's the infohash you send to the tracker when asking for peers. Hopefully from this explanation you can see that you need it for two purposes, one so you can give the right infohash to the tracker, and two so you can verify the data you receive from peers.
- samolang 13y agoWhat.cd is a private torrenting site. They decided to open source the code they use to run their site.
- sciurus 13y agoIt appears they decided to publish to code, but the license isn't open source as defined at http://opensource.org/docs/osd http://opensource.org/docs/osd
- slacka 13y agoSee my post above for links/references, but it was originally released under the GPLv3.
- dewey 13y agoA minor detail: The codebase was open source for a long time already, just on their own git and available on what.cd/gazelle and the IRC channel instead of GitHub.