In this release, the tracker has been rewritten to use asynchronous I/O, so it no longer has the hanging problems which plagued it before.That one barely worked at all this one is much better. A massive bug in the last release has been fixed.This should be the last backwards-incompatible release. The protocol has been reworked to be much more secure, and now uses a fixed port. Much better error-handling and multi-file support were added, so multiple files can be downloaded with a single click. Significant UI enhancements were made, including progress meters on file allocation and resuming. Major performance enhancements, including peers reciprocating uploads more responsively.There are a huge number of small stability and performance enhancements, none of them directly impacting the interface. The UI is much nicer, and now looks like a real GUI.Unix installation was simplified, and many small improvements were added. Usage of TCP buffering was also greatly improved. For this release, the upload/download logic was thoroughly rewritten to use a tit-for-tat bandwidth trading strategy.A clean shutdown, small improvements, and bugfixes added. The publisher now stores metadata in files, so it doesn't have to re-scan files every time it restarts, and the tracker now stores publisher and downloader information persistently, so downloads start working again as soon as it restarts. Monothreading was added which gave vast performance increases. It is now completely graphical and works in mozilla/netscape under UNIX.
It should now work under Windows and Mac OS X.
Table of versions released into the public domain or under MIT License The client also enables users to create and share torrent files. It also intermediates peering between itself, source file servers ("trackers") and other clients, thereby yielding distribution efficiencies. It has an automatic recovery system that checks all data that has been handled after an improper shutdown. A host of views offer information on the peers and seeds to which the user is connected, including how much data is being downloaded from each and to how much data is being uploaded by each. BitTorrent has several statistical, tabular and graphical views that allow a user to see what events are happening in the background. The current client includes a range of features, including multiple parallel downloads. The BitTorrent client enables a user to search for and download torrent files using a built-in search box ("Search for torrents") in the main window, which opens the BitTorrent torrent search engine page with the search results in the user's default web browser. As a result, it is no longer open source. Since version 6.0, the BitTorrent client has been a rebranded version of µTorrent. Version 4.20 of the client was dubbed Allegro by BitTorrent Inc., in reference to protocol extensions developed by the company to accelerate download performance and ISP manageability. Versions 4.0 and 5.3 were relicensed under the GPL. The source code for versions 4.x and 5.x was released under the BitTorrent Open Source License, a modified version of the Jabber Open Source License. Versions up to and including 3.4.2 were distributed under the MIT license. Very early versions released prior to Decemwere released into the public domain without a license.
Prior to version 6.0, BitTorrent was written in Python, and was free software. It is now maintained by Cohen's company BitTorrent, Inc.
Programmer Bram Cohen designed the protocol in April 2001 and released a first implementation of the BitTorrent client on 2 July 2001. As a result, it is no longer open source and is currently available for Microsoft Windows and Mac OS X. Since version 6.0 the BitTorrent client has been a rebranded version of µTorrent. It is often nicknamed Mainline by developers denoting its official origins. BitTorrent was the first client written for the protocol. used for uploading and downloading files via the BitTorrent protocol.