Understanding BitTorrent
BitTorrent is a technology for sharing data over the internet. A lot of people use it to download video and music files from the net quickly and easily, but it's not always legal. Here's what you should know before you hit the download button.
How does BitTorrent work?
BitTorrent became popular as broadband become more widely available, and as computers generally got much cheaper. In the early days of the internet, no one wanted to transmit very large files from one place to another. Now, everyone wants to do it. BitTorrent makes it easy.
The old way of moving big files was for one computer to connect to another, ask for the file, and download it in one huge chunk. If anything happened to interrupt that connection, the download had to be paused, and in some cases had to be abandoned and started again from scratch.
BitTorrent does things differently - here's a step-by-step guide on how it works:
- The source of the large file is called the 'host', and it creates a torrent file which is tiny - it just tells other computers what they need to know to reach the file that's being shared. What it's called, how big it is, and so on.
- The host slices the big file up into small pieces, and starts distributing (or 'seeding') them among a few of the other computers that want it - these are known as 'peers'.
- Each peer gets a few small chunks of the original file. Another computer - the 'tracker' - keeps an eye on which peer has got which piece. It acts as a central control point.
- All the peers keep in touch with the tracker, exchanging tiny chunks of data to make sure they know which piece of the file they need to get, and which other peers have got it.
- The smartest bit of the system is that the more peers join in with a particular torrent, the faster and more efficient it gets. More peers means more places for bits of data to be stored; everyone benefits.
This is the reverse of the old system, where large numbers of downloaders could easily bring a host to its electronic knees by making multiple requests for downloads.
How can I use BitTorrent?
If you want to download files by BitTorrent, you need to download some software called a BitTorrent client. The client manages your downloads for you.
If you use Windows, try the original BitTorrent or Opera. Mac users can also use Opera, or might like to try Tomato.
BitTorrent tips
It's important to realise that when you start downloading a torrent, you're allowing your computer to become a peer. You're not just downloading - you're also sharing what you've downloaded with other peers. Data is coming in, but it's also going out. In the torrenting community, it's considered bad manners to switch off your client or your computer right after downloading something - you ought to leave the client running for a while to help share the data with others.
Obviously you need a decent broadband connection for this, and also need to be aware of bandwidth limits. If your broadband provider caps your bandwidth at a certain number of gigabytes per month, you could easily reach the limit quickly if you download a lot of stuff.
Where do I find torrents?
There are many torrent search engines out there, and most client software can search for you as well. The most popular torrents can usually be found at specialist tracker web sites like The Pirate Bay, BTJunkie or Mininova.
Most of these sites provide links to material that is under copyright, and therefore illegal to own without having paid the copyright owner. The Pirate Bay is probably the best known, but attempts by the media industry to close it down have failed so far. Based in Sweden, the Pirate Bay has been taken to court but not been found to be breaking the law - not yet, anyway.
That doesn't mean that it doesn't provide links to illegal content that's being torrented. It does - there's loads of it. Music, movies, software; vast amounts of it pirated. The name "Pirate Bay" kind of gives it away, really.
Is it legal?
Having BitTorrent software on your computer is legal. Downloading files using BitTorrent is legal - depending on what sort of files they are.
In most countries, including the UK, it's illegal to download copyrighted material. So if you are torrenting a video that you made with your friends about your holiday in Greece, that's fine; torrenting a movie that's been copied from a DVD is illegal.
Downloading movies is illegal
American courts have already seen plenty of lawsuits against BitTorrent users, but so far no similar cases have made it to court in the UK. That said, anti-piracy authorities and private firms like Logistep have taken steps to demand server logs and IP addresses from Internet Service Providers (ISPs) - information that could lead them directly to millions of torrent users.
If you do torrent illegal stuff, remember that unless you're very experienced in computer networking, your activities will be logged somewhere along the line and you could end up facing a court summons.
Glossary
Peer - a computer that is taking part in a torrent by downloading and sharing chunks of the original file.
Host - the computer with the original file; it starts the torrent process off.
Seed - the first bits of data that get sent out by the host to the first peers that come along.
Tracker - a specialised computer that monitors torrents and remembers which chunks of data have been sent to which peer.
Client - software you use to find and manage your torrents.
Logs - electronic records of network activity, held by ISPs and other networked organisations.
IP address - The numeric code that identifies where your computer is on the internet. IP addresses can be tracked to particular locations or homes.
ISP - Internet Service Provider - the company that provides your internet connection.
Print this page Email this page to a friend Add to favourites
