Azureus' Swarm Feature

Adam Turner looks at file-sharing software that won't get you into trouble with the law.

SWAPPING files over the internet has long been a popular way to exchange pirate music, movies and television shows. But file-sharing technologies have a growing number of legitimate uses.

Most of today's file-sharing software is known as peer-to-peer, or P2P, because you're downloading files from other users rather than from a central site.

While Kazaa was popular several years ago, BitTorrent is the new P2P king. Both let you download a file from hundreds of users at the same time, whilst simultaneously uploading that file to other users.

BitTorrent is more efficient than Kazaa because it starts sharing the parts of a file you've downloaded before you've downloaded the entire file.

To use BitTorrent, you need to download software that lets your computer find other computers on the internet holding the files you want. You might need to adjust your firewall settings to let the BitTorrent software connect to the internet. Next, go to a BitTorrent search engine such as mininova.org or torrentspy.com and search for the file you want.

The file isn't stored at these websites, only a "torrent" file telling your computer where to find copies of the file. Download the torrent file, open it in your BitTorrent software and it will start downloading the file from other computers on the internet also running BitTorrent software. The more people sharing that file, the faster it will download.

The BitTorrent software presents you with a list of files you're downloading and uploading, along with the number of people you're connected to, at what speeds and how long the download should take.

Most BitTorrent software is free and using it is not illegal, although admittedly the vast majority of BitTorrent files shared across the internet are illegal copies of music and video.

Using BitTorrent for video files requires a broadband connection with a download limit of at least 1GB a month, as one episode of Lost is a 350MB file.

Telstra's BigPond internet service is one of the few in the country that counts uploaded data towards your monthly limit, so BigPond users need to keep in mind that while they download BitTorrent files they're also uploading.

Big business has come to recognise that BitTorrent is one of the easiest ways to distribute files across the internet.

BitTorrent.com has just launched a legitimate online video store and YouTube competitor Joost intends to use BitTorrent technology behind the scenes. The BBC also plans to make shows such as Red Dwarf and Doctor Who available via the high-definition Zudeo (zudeo.com) BitTorrent site. Unlike illegal copies, these legitimate services embed anti-piracy measures into the files.

The contenders

Azureus

Azureus is the Swiss army knife of BitTorrent software thanks to the ability to download extra features. It's a 9.5MB file, plus you'll need another 7.1MB to download Java (java.com/getjava). Set-up offers the choice of beginner, intermediate and advanced, along with an option to test your firewall settings. Azureus has the most user-friendly interface of the lot, with colour-coding to tell you how a download is going and pop-up comments to explain various features. It can automatically adjust your upload speeds so your connection doesn't choke.

www.azureus.sourceforge.net

uTorrent

uTorrent is slimmed-down BitTorrent and is only a tiny 173KB to download. The set-up includes a link to a speed-test site if you don't know your connect speed, as well as the option to test your firewall settings. It's easy to set your maximum upload speed to stop your connection choking, but uTorrent also features a bandwidth scheduler. You can set it to download only at night, which is perfect for people with internet plans that offer extra download limits after hours.

www.utorrent.com

BitComet

BitComet is a 5.3MB download, but it doesn't have a set-up wizard like the others. Like uTorrent, BitComet also lacks a little of Azureus's colour-coded user-friendliness, but makes up for it with extra features such as the ability to preview videos files while they're still downloading and a built-in chat tool. It's easy to set your maximum upload speed, plus it lets you open web pages within the BitComet interface, making it easy to search for torrent files.

www.bitcomet.com

Verdict

There are no duds here. Azureus has the most user-friendly interface and is well suited to beginners and experts, but it does chew up more processing power than the others. It also chews up more bandwidth because it's harder to set your maximum upload limit - bad if you're with BigPond.

uTorrent is a good set-and-forget solution, especially for those wanting to take advantage of higher off-peak download limits.

BitComet takes a little longer to get the hang of but its extra features make it a good choice for BitTorrent users who are ready to shed their training wheels.