Have you heard all the buzz in the news about how BitTorrent is destroying the music and video industry and how that people are going to jail and paying millions of dollars in fines for using BitTorrent? BitTorrent is an amazing technology for sharing large files and is not inherently evil (regardless of what the MPAA and the RIAA want you to believe).
Let's look at what BitTorrent is and what you can do with it. This can give you a head start on learning how BitTorrent works.
What Is BitTorrent?
BitTorrent is a technology invented by Bram Cohen in 2001 to share large files across a network. This network can be the Internet, or within a company's own intra net. This is often called peer-to-peer file sharing because individual computers help distribute the file instead of being completely dependent on a central server for the whole process.
Because of the way traditional file transfer works, you have to be constantly connected to the server that is handing out the file. If the connection is interrupted, then usually the file transfer has to start over. At the time the BitTorrent protocol was born, there were ways to resume a file transfer, but they were not as robust and error free as BitTorrent ultimately became. File transfers can be sabotaged by slow connections; either into or out of the server that is providing the file.
The BitTorrent protocol was also trying to overcome another problem. Since many large files were being transferred between individual users on the Internet, and not file servers, there was a big limitation on how many people could grab the file at any one time. The amount of available bandwidth was a problem when transferring a file from normal broadband, or dial-up connections, to other computers (called peers). Most consumer connections to the Internet are asymmetrical, which means that the person's download speed is different than their upload speed. This difference is that the download speed is always faster than the upload speed.
So, for example, if you had a large file that you wanted to share with your brother across the country and you both had the same speed broadband Internet connections, you would think that the file would transfer as quickly as his download speed allowed. But your upload speed is keeping you from giving the file to him as quickly as he is able to receive it. This means that for you to share with your peer, the connection is inherently much slower than if he were to grab it off of an Internet server which has faster upload speeds than standard Internet connections provide.
What Can BitTorrent Be Used For?
There are many reasons to use peer-to-peer file sharing technologies like BitTorrent. While some reasons are clearly illegal, there are legitimate uses for the BitTorrent protocol.
Many video podcast providers use BitTorrent to share the large video files of their free podcast. If you have used the Miro player to grab legitimate online video, then you have used a BitTorrent client.
Linux distributions and other open-source software often use BitTorrent to help distribute their programs. There are popular game manufacturers, Valve and Blizzard to name two, which have use BitTorrent to distribute some of their content.
Another use for BitTorrent is sharing marketing videos with the sales force of a company. A company may have created 50 GB of videos for their sales team, who work away from the office, to use. Since these workers are not in the corporate office, they don't have access to a high speed intra office network. If they were all in the office they could, realistically, transfer a file of that size in about 16 minutes (50 to 60 megabytes per second transfer on a Gigabit network is a real-world number). If doing the same thing over a fast Internet connection of 10 Mbps it would take about 7 hours in a "best case" example. During that time while using traditional transfer protocols, if either computer disconnected, the whole transfer would have to be started again. However, if the remote sales team of 200 people were using BitTorrent, then they could all work to transfer the file among themselves without having to worry about connection interruptions and accomplish the task in well under the time it would take for all 200 to connect directly to the office server.
These are very legitimate uses for BitTorrent and why someone might want to look into using it to transfer large amounts of data.
Is BitTorrent Evil?
As seen above, BitTorrent can be used in various legitimate ways. However, there are also ways that BitTorrent is used for illegal purposes. Cars can be used for illegal purposes too. So can just about any other tool we have available to us through the Internet, or that we can physically buy in a store. BitTorrent is just that: a tool. What the tool is used for, and how it is used can be either good or bad.
The RIAA and the MPAA (Recording Industry Association of America and the Motion Picture Association of America, respectively) would like everyone to believe that the only purpose for peer-to-peer technologies like BitTorrent is for stealing their music and movies. While there are people who use BitTorrent in that way, there are also proper ways to use BitTorrent. It is unfortunate that some companies and Internet Service Providers (ISP) have seen the need to block all BitTorrent traffic because of improper use.
It is illegal to share software, music and videos that you do not own the rights to. However, there are many things that you may be the creator of that you want to share with a select group of friends, or with the whole Internet. BitTorrent is a perfect option in that case.
Learning a little about how BitTorrent works will help you see good, legitimate uses for this technology. I go into a detailed, analog example of how BitTorrent works in another article. I do not attempt to explain the technical side of BitTorrent. It is a non-technical example of what the concept of using BitTorrent is and how it can be used effectively in a corporate or private environment.