BitTorrent Essentials


This article was published by ComputorEdge, issue #2849, 2010-12-03, as the cover article, in both their PDF edition (on pages 7-10) and their website.

One can think of the Internet as the ultimate global network, connecting together a variety of systems — ranging from the large internal networks within major international organizations, down to the single PC of a user at home, who may not even understand that his computer is part of a network. Riding on top of this worldwide Web of computers, is, well, the World Wide Web (WWW), which consists of an ever-growing pool of resources — text, graphics, video, etc. — connected together using hyperlinks within HTML documents.

At the heart of both the Internet and the Web, is the concept of sharing data and other resources. This sharing implies data transfer, such as when one's Web browser requests to load an image from a picture gallery website. There are a number of methods of data distribution over the Internet. The most common is Hypertext Transfer Protocol (HTTP), which is how the text and graphics on a Web page are transmitted from one or more Web servers down to the individual's computer, and viewed within her browser. File Transfer Protocol (FTP), just as the name suggests, is intended for the transfer of complete files, from one server to another, instead of individual Web components that have been formatted for display in a browser.

These two protocols may be the ones that Internet users are most familiar with, but there are some others, for instance, peer-to-peer (P2P) networking. In simple terms, the majority of the P2P networks function in the following manner: Every participant who is logged into a particular P2P network, is doing so via software that supports the given network and is running on that person's computer. The software makes it possible to see the files being shared by everyone else currently logged in to that same network. It also allows the individual to designate which files on his own computer — or multiple computers, if he has them networked together — he is willing to share with everyone else. If and when someone else on the network searches within her P2P software for a file that he has offered to the world, then she can request that the file can be copied from his computer to hers, within the network.

Peer-to-peer networks have been around for many years, and you may have heard of some of the more famous ones, such as Napster, Direct Connect, eDonkey, FastTrack, and Audiogalaxy. They have largely been swept into the dustbin of Internet history — at least in terms of unfettered sharing. But in their heyday, they were remarkably popular. In fact, for the more heavily used networks, multiple front-end applications were developed by programmers; for example, the Gnutella P2P network was accessible using such programs as BearShare, Grokster, iMesh, LimeWire, and Shareaza.

A Stream of Data

As those older, more "closed" P2P networks die off, greater attention has been focused on what appears to be the sole survivor: the BitTorrent network. Quite unlike those other networks, BitTorrent uses a different method for sharing files among participants. It is based upon an ingenious approach known as "file-swarming", in which the source file is divided into smaller pieces — each referred to as a "torrent" — and then shared among all the people who have requested that file. Anyone who is offering copies of a file on the network, is referred to as a "seeder", and anyone who is currently downloading the file but not yet uploading its pieces, is referred to as a "leecher". This has led to people often advising others, "Seed this file!" The more seeders there are for any given file, the easier it is for others to download it, and the faster the process, because there is less burden upon the bandwidth of the seeders.

In effect, BitTorrent leverages the power of a group of individuals who are sharing pieces of a file with others, and by doing so significantly increases the odds that any participant will be able to download all of the pieces that compose a particular file. To put it another way, you are able to download the various pieces of a single file from multiple participants, which in turn makes the entire network more redundant, because as long as there are multiple seeders, the odds are practically 100 percent that at least someone has any given part of the file. Naturally, if there is only one seeder, then you would need to download all the pieces from that person. But then once that process has finished, you can now become a seeder yourself, helping others. Best of all, you don't need to worry about any of the technical details, because the BitTorrent network, working in conjunction with the client programs, handles all phases of the process.

Consequently, BitTorrent is considered a major improvement over the aforesaid peer-to-peer networks, each of which was reliant upon a user downloading an entire file from a single user within the network. This meant that if the person making the file available were to suddenly disconnect his computer from the Internet, before you had finished downloading the file, then you would end up with only part of it, making the file of little or no value to you. If the file consists of music, such as an MP3 file, then you might only obtain the first few minutes of the composition, and the rest would be chopped off. If the file is an executable program, then having just a portion of it is completely useless.

Because the typical download is not relying upon a single connection to another person's copy of the file, it usually takes less time for you to download a seeded file. That's the reason why BitTorrent file-sharing is considered faster than the earlier P2P networks. This is analogous to the parallel processing that can be performed by multiple microprocessors when they divide up some computational task among themselves. Similarly, a multithreaded computer application can divide processing steps among multiple threads within a single instance of the program, which oftentimes speeds up the overall process.

There is an additional speed advantage that is rarely if ever mentioned by the average industry commentator: People using BitTorrent are generally more technically savvy than those using the older networks, and the former group will usually have faster broadband connections to the Internet, thereby making it quicker for you to download any files that they are sharing.

Another disadvantage of the conventional networks, is that the client programs that people used for interfacing with a network were oftentimes polluted with spyware and annoying pop-up advertisements. Fortunately for BitTorrent users, there are many client programs from which they can choose, and most of them are completely free of advertising and malware. Some of the choices include BitLord, BitTyrant, μTorrent, Vuze, and Xtorrent.

A Torrent of Controversy

As one might imagine, the original peer-to-peer networks came under heavy criticism from the music industry, because most of the traffic on those networks consisted of pre-recorded music from the world's favorite recording artists, and the music industry viewed this as cutting into sales revenue. As a result of the tremendous political and legal pressure exerted by the Recording Industry Association of America (RIAA) and later the Motion Picture Association of America (MPAA), most of the early (non-BitTorrent) networks were shut down, or forced to begin policing the files available on their networks to keep out the copyrighted material. This in turn greatly diminished the popularity of these networks.

Nonetheless, when those networks were still heavily used, and BitTorrents were gaining in usage, the RIAA and MPAA began taking legal action against people sharing files owned by their member recording companies. These industry organizations hire media security companies to locate songs being shared, identify the IP addresses of those files on the P2P networks, and then pressure the Internet service providers to turn over the names and addresses of their customers using those IP addresses. Once the RIAA, for instance, would learn the identity of anyone sharing music files, it would send him a cease-and-desist letter, along with a settlement offer, oftentimes in the tens of thousands of dollars. If the individual failed to agree and pay up, the RIAA would file a lawsuit to obtain damages in court.

Many of the early recipients of these settlement offers simply acquiesced, instead of trying to battle the music industry juggernaut. (One may wonder how these people came up with such large sums of money.) However, some folks have fought back, including someone who has now become well known in this ongoing war. Jammie Thomas, a Native American living in Minnesota, was accused by the RIAA of downloading and sharing 24 copyrighted songs in February 2005, on the Kazaa network. She was sent the usual cease-and-desist letter and settlement offer, but refused to pay, and was consequently sued by a number of record labels. After several years of legal battles and judgments against her, the statutory damages went from $9,250 per song (a total of $222,000) up to a shocking $80,000 per song ($1.92 million total).

This case, generally known as Capitol v. Thomas, may be the most well-publicized file-sharing lawsuit — and was the first tried before a jury. But it is only one of the many thousands of lawsuits filed against people using file-sharing networks, and the figures keep increasing. One may wonder if at some point the music and movie companies will relent, especially now that everyone is far more comfortable with the idea of purchasing and downloading individual songs from online vendors, such as Apple's iTunes and

Neither side has completely capitulated, and thus the battle between file sharers and copyright enforcers is ongoing. Much of the details can be followed in the online media. People on the side of file sharers can view some of the latest reports at TorrentFreak, among other related sites. People who agree with the copyright enforcers can peruse the sites of the RIAA and MPAA. These trade groups are specific to American companies; similar organizations exist for other developed countries.

Regrettably, all of the legal controversy and bad press have besmirched BitTorrent, which can be utilized for fully legal purposes. As an illustration of this idea, consider the increasing number of companies now distributing their free digital products in the form of torrents. This not only demonstrates their support of BitTorrent as a concept, but allows those organizations to reduce their own bandwidth costs, which can be greatly distributed among people who have an interest in those products. Moreover, listing those files on BitTorrent seed sites can make the products known to people who otherwise would never learn of the company or what it has to offer. An example of this is the Linux distributions that are commonly made available via BitTorrent.

Yet the popularity of BitTorrent certainly does not ensure its longevity into the future. If you would like to experience this remarkable resource before it is completely clobbered by trade organizations and government officials, try it now, while you still can.

Copyright © 2010 Michael J. Ross. All rights reserved.

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