Something else that confuses me about torrents
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Once someone downloads the tiny torrent file itself, why does the website have to be "up" to transfer the files?
It seems to me that the torrent website (in this case GTRU) is only hosting the tiny torrent files. Why is it that when a torrent website is down, the files associated with the torrents don't transfer? -
It is strange for me, I can usually download torrents when my browser is closed.
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You don't have to have the website open in your browser to download and strictly speaking, the website itself doesn't need to be up for the torrent to download.
The thing that needs to be up, is the tracker, which could live on the same server as the website, but often will have it's own server, or in a larger tracker, several servers.
The job of the tracker, is to keep track of who is offering what files, and who is downloading files.
For example, let's imagine you download the torrent file for a file I'm seeding. That torrent file includes some information about the file itself, and most importantly, uniquely identifies it to the tracker, and identifies that it's the GTRU tracker that's being used. You download the torrent file, this is read by your torrent client on your machine, and the info in the torrent file, tells the client that it needs to connect in this case, to the GTRU tracker.
My torrent client has been updating the GTRU tracker saying "I'm offering this file" When your client tells the tracker it want's to download the file, the tracker says "Go to MeatHook's machine, he's offering it." Without the tracker to tell leechers where the seeders for a file are, the whole thing would fall apart.
That's greatly simplified of course, but it's the essence of what goes on. It's the tracker that does the work, not the website in this instance.
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In addition:
Torrent's for private trackers, like GayTorrent.ru's, have the "private" flag set. Some call that a Digital Rights Restriction (DRM), because if a torrent client respects that flag, all good do, it allows only peers from the tracker. That means only peers which are members of GayTorrent.ru and have a valid passkey can get the IPs of other peers.
In opposite to that, public tracker torrents, like those indexed on The Pirate Bay or KickassTorrents, don't have that flag set and the client can get peers through other mechanism like DHT (Distributed Hash Table), PEX (Peer Exchange) and Local Peer Discovery.
So once the tracker isn't up and running, or the torrent removed ("unregistered torrent"), the clients will no longer get IPs of peers from the tracker. As long as the peers already known by the client continue to run the torrent, the exchange of the file can continue. Some clients like µTorrent don't save the peers information when shut down, others like qBittorrnt do, but as IPs are often given dynamically or peers seeing the torrent turning "red" stop it, exchange will stop sooner or later.
