Microsoft works on own BitTorrent

Microsoft researchers in Cambridge, UK, are developing their own peer-to-peer file-sharing software. Codenamed Avalanche, the program makes it easy to share content by dividing files such as software, audio or video, into chunks, much like BitTorrent. Using "network coding", it can re-create missing blocks of data that can be used in place of missing chunks.

In BitTorrent systems, server sites do not host the files being shared. They host links, called "trackers" that direct people to where they can the pieces of a file instead.

But unlike BitTorrents, Avalanche does not depend on trackers. The Avalanche program on each computer shares the files automatically, without having to search a user's hard drive.

The problem with many file-sharing applications is that not all the pieces to make a complete file may be obtainable.

Sometimes there is heavy demand on the file-sharing network, which can slow download times, when people try to find missing parts.

Through its network encoding, Avalanche is designed to rebuild the required part of a file once it has enough other pieces of a file to work on; this means Avalanche can turn any part of a file into what it needs.

Microsoft says that the system stops people re-distributing content because it will only forward files that have been "signed" by the publisher.