25 Apr 05
Advanced BitTorrent Topics
Sharing your own files
Now that you have a handle on how to download files with BitTorrent and BitTornado, you may want to share some files of your own. It's not difficult, but you will need three things: First, you will need a BitTorrent Client, such as BitTornado. If you've read this far, you should already have that. See the section of this guide on installing and configuring BitTornado if you don't. Second, you are going to need a broadband internet connection that is always on. Cable or DSL should be sufficient, but a LAN connection with a T-1 would be even better.
The last thing you will need to share your files with BitTorrent is a tracker. The tracker is a small file running on a web server that tells everyone who is trying to download the file where the file is available.Trackers can track many different files at the same time, so you should be able to find someone who is willing to let you use their tracker. Try a Google search for BitTorrent Trackers to get you started. All of the big BitTorrent sites have trackers, and some of them will let you use theirs. There is also a lot of information on trackers, including how to create your own, in the README.txt file in the BitTorrent source distribution.
Once you have collected everything you need, the first step is to create the .torrent file. There are many programs out there that will do this for you. The original torrent creating program is called CompleteDir, and is available at SourceForge.net. Tell CompleteDir what the URL (web address) of your tracker is, and it will create a torrent file. Upload that torrent to your web site (or any web site) so that people can download and run it.
The last thing you have to do is seed the file. You have to start the first seed, or there will never be anyone to get the file from. To seed the file, run the torrent file you created just like any other BitTorrent download.
When your BitTorrent client opens up, point it to the file on your computer you want to seed. Your BitTorrent client will verify the integrity of the file and then begin to seed the file to anyone trying to download it. Leave your client open for as long as possible to help get as many complete copies into circulation as possible.
The newest version of BitTorrent supports trackerless seeding. Basically, it uses each client that is downloading the file as a mini-tracker, eliminating the need for a separate tracker. This method of seeding files may never be as reliable as the tracker method, but it greatly simplifies hosting and seeding files with BitTorrent. All you have to do is make a torrent and put it on a web site. More information on trackerless seeding is available on the Official BitTorrent Web site.
Broadcatching is a way to automatically download a file with BitTorrent through an RSS feed. Suppose you are really interested in Ubuntu Linux, and you like to stay up to date with the latest patches and distributions. With broadcatching, Ubuntu could distribute a torrent to the latest release through RSS, and your BitTorrent Client would automatically download it.
Unfortunately, this is only an example of what is possible. Boradcatching is a very new concept and Ubuntu does not currently participate. There are a few sites using broadcatching to distribute independent radio and video broadcasts (termed "podcasts"), and I'm sure the concept will be adopted by other content providers very soon. The potential for broadcatching is enormous. I can envision broadcatching being used to distribute everything from software patches and service packs to subscription TV services in the near future. Lots of good information on broadcatching is available in this wiki.
Azureus has integrated support for RSS and broadcatching feeds.
If you are interested in sharing your own files or in broadcatching, you should look into Blog Torrent. Blog Torrent is an open source php script you can run on your web page which is designed to help you share your files through BitTorrent. It does several things, the most impressive of which is acting as a tracker. You can run a tracker from your web site, and it's really easy to set up.
Also with Blog Torrent, visitors to your web site don't have to know anything about BitTorrent to download your files. If they don't have BitTorrent on their computer already, Blog Torrent will automatically install a BitTorrent client on their computer when they click on your download.
Blog Torrent also can supply an RSS feed. Visitors to your web site can subscribe to that RSS feed and automatically download any files that you post, creating your own broadcatching feed. Blog Torrent was designed with video weblogs in mind, but you could use it to help your readers stay current with the software you are developing or even to run a podcast.
Questions? Comments? Suggestions? Contact me.
20 Sept 07