BitTorrent 3.2.2a (Donationware)
Bram Cohen & Andrew Loewenstern

Following up on the last Gadget, which offered one way to speed up your downloads, we present another method for helping get files to your Mac as quickly as possible. Although Speed Download does a fine job of maximizing your connection to a single file server, BitTorrent introduces a different model. Why focus on a single server, when there's bandwidth to spare from others who have already downloaded the file in question?

A BitTorrent system consists of several parts. One is a tracker, which keeps track of who is downloading what. Another part is a Web server, which is used to serve the file in question. Another is the client, which contacts the tracker when it needs to download a file, or to alert the tracker to a file that is available for download. But this is where is gets interesting. The BitTorrent client not only acts as a client, but also as a server to others who would like to download a file that you've already downloaded.

Download and Upload at the Same Time

BitTorrent works its magic in a few ways. The first is that when you request a download, the BitTorrent tracker will search for others who also have the file available, and open connections to them and start downloading pieces of the file. The other piece of magic is that once you start a download, the portion(s) that you've downloaded are also made available to others. As long as everyone contributes bandwidth as well as consume it, BitTorrent makes for a very nice distributed download system. Once you are finished with a download, you are encouraged to keep your client open, so that others can benefit from the file you've already downloaded.

Hey John, are there any uses for BitTorrent other than piracy? The quick answer is yes, there are legit uses other than piracy. BitTorrent is, after all, just a protocol. Unlike Napster, the nature of the content is not specific, you could use it to distribute any sort of file, but the style of content I saw offered leads me to believe that it is being used more for good than evil. The longer answer is that I ran into this while trying to get a copy of the somewhat (in)famous "Star Wars Kid" movie. I'm sure you heard of this little Internet event, if not, check out the link above. That's a perfect example of the many sorts of non-piracy uses BitTorrent is used for. The other niche this platform seems to have attracted is those who like to get tapings of live concerns. While this may also seem to raise the piracy flag, the bands that I've seen advertised (Phish, Dave Matthews) permit taping of their stuff, just like the Grateful Dead. Yes, I went to quite a few GD concerts... The nature of the protocol lends itself to the hippie-yippie nature of some of these bands' followers; take what you need, give what you can.

BitTorrent for Mac OS X acts as a helper application for some Mac browsers, such as IE and Mozilla. For some other browsers, such as Safari and OmniWeb, you'll need to cut and paste the .torrent URL into the BitTorrent client to get things started.

So start downloading and sharing files at the same time, and give BitTorrent a spin.

Have any other Gadgets that help you spread the joy? Send John an e-mail, and he'll kick it around.