Everyone loves to get something for nothing, but there is usually a hidden cost associated with any promise of gain without effort. Such is the case with a new BitTorrent client called BitTyrant, whose authors claim will increase download speeds by an average of 70 percent over standard BT clients.

BitTyrant does its magic by monitoring other connected users' upload speeds, and prioritizes those with faster upload connections. For example, if most clients are sending at 10KBps and BitTyrant detects that one file sharer can upload at 20KBps, it will "choke" the other users while bumping the priority of the faster uploader. In addition, it will dynamically increase its sending rate to this uploader.

While this system would appear to reward those with faster connections with greater download speed, it does so at the expense of the entire group of connected users. The BitTyrant web site even acknowledges this in its FAQ section. In response to the question: "Won't BitTyrant hurt overall BitTorrent performance if everyone uses it?" the FAQ says, rather coyly, "This is a subtle question and is treated most thoroughly in the paper. The short answer is: maybe."

Some users worry that if BitTyrant becomes popular, it could create unfavorable downloading conditions for people with low upload speeds, which include most cable and DSL connections. If too many users are being deprioritized for having low upload speeds, the overall transfer rate for torrents will go down, at least until the high-speed users finish sharing with each other. One thing BitTyrant will do that could be considered positive is that it will deprioritize users who deliberately throttle back their uploads, although this may have the side-effect of grinding new downloads to a halt, as users who have not yet been able to download any part of a file will be limited in what they can upload.

There are those who will argue that BitTyrant is simply a case of karmic justice, as many people consider BitTorrent to be little more than a vehicle for people to download copyrighted content for free. However, this is far from the whole truth. Many people use torrents to share legitimate files, including videos distributed through the Creative Commons (such as Bob Cringely's excellent NerdTV series) and the protocol is also used by software developers to provide demonstration versions of their products.

In the mean time, some users are already considering blacklisting BitTyrant users from their servers.
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