BitTorrent Official (Mainline) Client

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Today BitTorrent is everywhere. It is one of the dominant p2p networks, and accounts for a quite large percentage of total internet traffic. There are tons of clients, hundreds of sites with files, and millions of torrent files out there. But in 2002 there was just one client, and a very limited number files on an even smaller number of sites. For info on why it caught on so well check out the what is bittorrent page.

Back then each download would open in a separate window. You couldn't minimize it to the system tray. And for many users with asymmetric connections (like cable), running bittorrent created problems for users. It would quickly max out the upstream speed. This made other internet tasks, including simple web browsing be painfully slow.

But it was open source. Soon Eike Frost came out with an 'experimental client', used mainly because it could cap the upload speed to make the rest of the internet usable. Soon other clients came along, including many with different GUI's that could download multiple torrents in one interface.

Since 2002 Bram Cohen has released many updates to the official client. Some of them were improvements to the protocol itself, and others were adding features to his client. The latest group of updates made a big step forward after a long break in between releases.

Version 4 added some much needed features to the official client. It now has a multi-download GUI. This leaves BitTornado as the only client that uses separate windows for each torrent (although that may soon change as well). Another important advance is the sliding bar for the max upload speed, ranging from 4 KB/s (dialup) to 7.8 MB/s (OC3). Both these features have been in most other clients for some time. The max upload thing can be very important, most cable/dsl users find if this is not capped around 85-90% of your max upload speed, even tasks like web browsing can become very slow while using BT.

You can also get some more info on the torrents easily, like the tracker being used and the file list if it is a multi-file torrent. A play/pause function, viewing the peer list, easy port changing, automatic seeding guidelines, and a default download folder are also available. It also allows you to change what IP is reported to the tracker. I believe this version can download all files via a single port, like several other clients have done for a while.

The Shad0w came out with a function called superseeding for his client a while back. Without going into too much detail, starting a new torrent with regular seeding could require 150-200% of the file size to be uploaded because pieces are sent randomly, regardless of wether or not it has been sent before. Superseeding plays games to get this number down to around 105%. Version 4 of the official client supposedly eliminates the need for superseeding.

The current beta is developing trackerless support. Azureus was the first to do this (after eXeem's attempt), and Bit Comet joined the group as well now. Bit Comet and this client use the same trackerless system, but Azureus's system is incompatible with other clients..

While this client has some much needed additions, it still lacks the amount of the features many others now have. Things like downloading individual files from a multi-file torrent can be done in Azureus or BitTornado, but not the official client. This client should work great for occasional downloaders, and those having compatibility issues with other clients. But power users will likely still choose to use another client.