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Bittorrent: An explanation of the Protocol

What is BitTorrent as a technology?

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BitTorrent is a technology that is mainly used in the sharing of large files, though it is also favorable in achieving maximum redundancy of a file on the internet. Basically the technology is a Peer-to-Peer system, in which clients (your personal computer) connect to a central tracking server, the “tracker”. This “tracker” keeps track of all the “peers” connected to a single file that is being shared on the network. When peers connect to the server they begin to capture bytes of the file that is being downloaded and in the same likeness begins re-uploading those bytes to allow other “peers” to get at the file being downloaded. The action of re-uploading is also called “seeding”, which allows other “peers” connected to this file to get a maximized connection for download. All in all, it can be summarized as being a file sharing service.

What’s the controversy?

The controversy around the use of BitTorrent technology lies in the notorious connotation that the technology has with enabling copyright infringement. Infamous torrent trackers make headline news as they are among some of the most trafficked websites in the world. According to the Alexa Internet Site Ranking service, the 217th most trafficked website in the world is a known torrent tracker. People are very aware of these websites, but if they are unfamiliar with the technology and what it means to be a patron to these sites, they can suffer consequences that can impact their lives severely.

What’s “seeding”?

Seeding is the act of uploading to a torrent data stream. As a key part of the technology, seeding is what allows for data redundancy when other seeders go offline, as well as a boost to overall throughput/data speeds when other peers want to download a file. As a seeder you connect to the torrent network, and other peers are able to see where to retrieve data for the file they want to download. The way the download works is based on a network identifier known as an IP Address, so every “peer” connected to the same torrent are either uploading or downloading and are known to every other “peer”.

What’s being a “peer”?

A peer is anyone connected to a torrent file, and downloading or uploading data to the collective network.

What’s being a “leech”?

A peer who rather than committing to upload and download data, is stopping their clients uploading to resist contribution to the collective network.

BitTorrent Protocol Diagram

BitTorrent for legal and legitimate use.

BitTorrent can be legally used for file transmission, when the material isn’t subject to Copyright, some materials such as open-source software or media with Creative-Commons licenses can be subject to a lesser extent of Copyright, and are often okay to distribute freely. One such site that takes advantage of the BitTorrent protocol is http://linuxtracker.org/ where individuals can download various distributions of the free and open-source Linux Operating System using BitTorrent.

What are the consequences of infringing copyright?

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Because of the Digital Millennium Copyright Act enacted in 1998, any person caught violating a copyright owners exclusive rights, can be penalized in ways where the violator would have to pay damages, being forced via injunction to stop infringing activities, and potential jail-time. As a UMass student you are also subject to the policies of Copyright and Fair Use instituted by the University, which outlines penalties for violating Copyright.

UMass Copyright Policies: http://www.it.umass.edu/copyright/copyright-umass-amherst-higher-education-opportunity-act-information

Source: https://www.lib.purdue.edu/uco/CopyrightBasics/penalties.html