BitTorrent is a fast and efficient way to swap files
If you’ve ever read about music piracy, you probably have heard of BitTorrent. With the record industry taking hundreds of its users to court, BitTorrent has become known as one of the Internet’s bad boys.
Despite this, the majority of computer users are unfamiliar with how it works and why it legally can be useful.
At its simplest form, BitTorrent is a protocol for transferring files between personal computers. This distribution method is referred to as peer-to-peer or just P2P. Its strength lies in using many personal computers to transfer different pieces of a file to one downloader. This can be more efficient than a single server satisfying many download requests.
Perhaps the best way to illustrate this is an example. Movies that have fallen out of copyright are fine to download; say a user wants to download “The Gold Rush” with Charlie Chaplain. One option is to find a single site with a download link and transfer it.
However, a more efficient way would be to look on a BitTorrent site (in this case probably legaltorrents.com). Once the user finds “The Gold Rush” and clicks on it, a small torrent file is downloaded. Any one of several free programs can open the file, which is essentially a set of instructions on how to connect to the tracker for that file.
The tracker is a traffic director that sends a download request to the rest of the personal computers sharing that movie file. For the sake of this example, 100 people — called seeders — are sharing the movie. The tracker requests those 100 seeders to start sending pieces of the file to our user’s computer.
Transfer speeds depend on how many seeders are online and how fast their computers can upload the file. With popular files, download speeds on a computer may be two or three times faster than a normal Internet (HTTP) request.
Such a leap forward in file transfer technology allows large files to be moved quickly, while also precluding the need for one entity to transfer files to many others. In this way, the BitTorrent protocol saves money by reducing the amount of money a single host must pay for bandwidth (the amount of data that can be transferred).
On the other side of the coin, content distribution to the masses suddenly becomes much easier. Many independent bands are finding that a few fans can help spread around sample songs quite quickly. Where an artist once needed a huge record company staff and independent promoters to gain a large audience, the Internet and BitTorrent make that distribution far simpler.
So is BitTorrent the bad boy of the Internet? Technology can be (and often is) used to break the law. However, BitTorrent has also made life easier for seekers and swappers of legitimate, legal content. Best of all, it provides part of the solution to the problem of using bandwidth to transfer large files. As we demand more from our computing and surfing experience, content providers will begin to struggle to satisfy requests quickly and economically.
To read more about BitTorrent, go to wired.com/wired/archive/13.01/ bittorrent.html. This piece by Clive Thompson features an interview with the creator of BitTorrent, Bram Cohen. To learn more specifically about how BitTorrent functions, try bittorrent.org/beps/bep_0003.html.