BitTorrent client
Encyclopedia
BitTorrent is a peer-to-peer
Peer-to-peer
Peer-to-peer computing or networking is a distributed application architecture that partitions tasks or workloads among peers. Peers are equally privileged, equipotent participants in the application...

 program
Computer program
A computer program is a sequence of instructions written to perform a specified task with a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute...

 developed by Bram Cohen
Bram Cohen
Bram Cohen is an American computer programmer, best known as the author of the peer-to-peer BitTorrent protocol, as well as the first file sharing program to use the protocol, also known as BitTorrent...

 and BitTorrent, Inc. used for uploading and downloading
Uploading and downloading
In computer networks, to download means to receive data to a local system from a remote system, or to initiate such a data transfer. Examples of a remote system from which a download might be performed include a webserver, FTP server, email server, or other similar systems...

 files via the BitTorrent protocol. BitTorrent was the first client
Client (computing)
A client is an application or system that accesses a service made available by a server. The server is often on another computer system, in which case the client accesses the service by way of a network....

 written for the protocol. It is often nicknamed Mainline by developers denoting its official origins. Since version 6.0 the BitTorrent client has been a rebranded version of µTorrent. As a result, it is no longer open source
Open source
The term open source describes practices in production and development that promote access to the end product's source materials. Some consider open source a philosophy, others consider it a pragmatic methodology...

 and is currently available for Microsoft Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

 and Mac OS X
Mac OS X
Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...

.

History

Programmer Bram Cohen
Bram Cohen
Bram Cohen is an American computer programmer, best known as the author of the peer-to-peer BitTorrent protocol, as well as the first file sharing program to use the protocol, also known as BitTorrent...

 designed the protocol in April 2001 and released a first implementation of the BitTorrent client on 2 July 2001. It is now maintained by Cohen's company BitTorrent, Inc.

Prior to version 6.0, BitTorrent was written in Python
Python (programming language)
Python is a general-purpose, high-level programming language whose design philosophy emphasizes code readability. Python claims to "[combine] remarkable power with very clear syntax", and its standard library is large and comprehensive...

, and was free software
Free software
Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...

. Versions up to and including 3.4.2 were distributed under the MIT license
MIT License
The MIT License is a free software license originating at the Massachusetts Institute of Technology . It is a permissive license, meaning that it permits reuse within proprietary software provided all copies of the licensed software include a copy of the MIT License terms...

. The source code for versions 4.x and 5.x was released under the BitTorrent Open Source License
BitTorrent Open Source License
The BitTorrent Open Source Licence, is derived from the Jabber Open Source Licence, which is an Open Source Initiative approved license. Former versions of the BitTorrent client and related pieces of software are licensed under this License which is available here:...

, a modified version of the Jabber
Extensible Messaging and Presence Protocol
Extensible Messaging and Presence Protocol is an open-standard communications protocol for message-oriented middleware based on XML . The protocol was originally named Jabber, and was developed by the Jabber open-source community in 1999 for near-real-time, extensible instant messaging , presence...

 Open Source License. Versions 4.0 and 5.3 were relicensed under the GPL
GNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....

.

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.

Since version 6.0, the BitTorrent client has been a rebranded version of µTorrent. As a result, it is no longer open source
Open source
The term open source describes practices in production and development that promote access to the end product's source materials. Some consider open source a philosophy, others consider it a pragmatic methodology...

.

Features

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
Web search engine
A web search engine is designed to search for information on the World Wide Web and FTP servers. The search results are generally presented in a list of results often referred to as SERPS, or "search engine results pages". The information may consist of web pages, images, information and other...

 page with the search results in the user's default web browser
Web browser
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier and may be a web page, image, video, or other piece of content...

.

The current client includes a range of features, including multiple parallel downloads. BitTorrent has several statistical, tabular and graphical views that allow a user to see what events are happening in the background. 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. It has an automatic recovery system that checks all data that has been handled after an improper shutdown. It also intermediates peering between itself, source file servers ("trackers") and other clients, thereby yielding distribution efficiencies. The client also enables users to create and share torrent files.

BitTorrent DNA

BitTorrent DNA (BitTorrent Delivery Network Accelerator) is a program designed to speed up the viewing of streaming video, downloading software (with or without the BitTorrent protocol) and playing online video games. It does so by distributing the end users' downloads between each other. In this way, the developers intend that content providers should take less load on their servers so the end users can receive the content faster. It runs in the background whenever the operating system is running.

BitTorrent DNA is different from traditional BitTorrent in that it relies on publisher HTTP
Hypertext Transfer Protocol
The Hypertext Transfer Protocol is a networking protocol for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web....

 servers in order to provide publishers with guaranteed minimum data delivery rate, as well as give publishers control over content delivery (peers must connect to the origin server before they can reach other peers), and collect information about content delivery to share with the publisher. The quality of the file transfer is specified in terms of a long-term average bitrate for data and in terms of meeting deadlines when streaming. It also can give bandwidth to TCP
Transmission Control Protocol
The Transmission Control Protocol is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite, complementing the Internet Protocol , and therefore the entire suite is commonly referred to as TCP/IP...

 and other traffic.

DNA is also different from traditional BitTorrent in that it is a UDP
User Datagram Protocol
The User Datagram Protocol is one of the core members of the Internet Protocol Suite, the set of network protocols used for the Internet. With UDP, computer applications can send messages, in this case referred to as datagrams, to other hosts on an Internet Protocol network without requiring...

-based protocol that has replaced regular TCP-based bandwidth
Bandwidth (computing)
In computer networking and computer science, bandwidth, network bandwidth, data bandwidth, or digital bandwidth is a measure of available or consumed data communication resources expressed in bits/second or multiples of it .Note that in textbooks on wireless communications, modem data transmission,...

 throttling with a much more sensitive bandwidth management technique.

Apart from being installed by third party
Third-party software component
In computer programming, a third-party software component is a reusable software component developed to be either freely distributed or sold by an entity other than the original vendor of the development platform...

 websites and software companies, the program for end users is also installed when the official BitTorrent client is installed (starting with the rebranded version 6.0). However, it can be independently uninstalled.

The first version of the DNA made it possible to keep the DNA application installed and yet temporarily stopped until the next system restart (through the system's control panel, in Windows XP
Windows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...

). The DNA GUI
Graphical user interface
In computing, a graphical user interface is a type of user interface that allows users to interact with electronic devices with images rather than text commands. GUIs can be used in computers, hand-held devices such as MP3 players, portable media players or gaming devices, household appliances and...

 was completely removed in the official BitTorrent version 6.1 and 6.1.1, but was re-introduced in version 6.1.2.

Since October, 2007 BitTorrent DNA has been offered by BitTorrent, Inc. as a commercial service that content providers can purchase (for an undisclosed price) and as a free background program for end users. Company President Ashwin Navin
Ashwin Navin
Ashwin Navin was the President and Co-Founder of BitTorrent, Inc. He joined Bram Cohen, the inventor of BitTorrent, in 2004 and reportedly handled business and company-related matters while Cohen focused on engineering and product development...

 launched the product claiming that "Implementing BitTorrent DNA on top of legacy infrastructure has the profound impact of allowing our customers to deliver a better user experience, higher quality video, faster software downloads, all with the security and reliability of a managed service."

Navin in a podcast
Podcast
A podcast is a series of digital media files that are released episodically and often downloaded through web syndication...

 interview claimed that he attempted to sell BitTorrent DNA in January 2005. After finding that BitTorrent's brand was too polarizing for potential customers, they delayed the launch until after partnering with nearly 50 media companies in the BitTorrent Entertainment Network. That provided the company enough public validation to finally launch BitTorrent DNA two and half years later.

The service's first customer was the company Brightcove
Brightcove
Brightcove is a Cambridge, MA based company that produces an Online Video Platform .- History :Brightcove was founded in 2004 by Jeremy Allaire, who now serves as CEO. In March 2006, Brightcove acquired Seattle-based Metastories, makers of StoryMaker, a publishing tool for video, audio, images, and...

, that chose to use it to distribute streaming video files.

As of May 2009, the Asus
ASUS
ASUSTeK Computer Incorporated is a multinational computer technology and consumer electronics product manufacturer headquartered in Taipei, Taiwan. Its product range includes motherboards, desktops, laptops, monitors, tablet PCs, servers and mobile phones...

support website is using BitTorrent DNA as an additional download method of their larger files in addition to their multiple somewhat internationally distributed HTTP servers and content delivery mirrors and other redirection facilities Asus has been known to rely in the present and past for their data delivery needs. Currently, a separate "P2P" icon is being presented for the DNA style downloads next to the "Global" and "Chinese" located servers as an example.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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