Maximizing Bittorrent downloads

There are several things you can do to ensure you get fast downloads when using the Bittorrent P2P network. Most client software has a good help file; my personal choice is Transmission. Here are a few things to consider when setting up your bittorrent software.

1. Ensure your BT client software is set up to forward your port. This makes it easier for others to connect to you, which in turn increases your speed. Port forwarding is simply creating a rule that maps an incoming connection to your router to a computer on your network. Hence, there is no delay as your network tries to figure out which computer to send the data to. Port forwarding help, including how to set up many different brands of routers, can be found at http://portforward.com/default.htm.

2. You need to cap your upload speed to ensure your connection doesn’t get flooded. From personal experience, this is probably the trickiest part to figure out. According to the Transmission help file, a rule of thumb is 60-70% of your max upload speed. However, most people don’t know what their upload speed limit is; often they don’t know what their download speed is. If you go to Broadband Reports, you’ll find a comprehensive test suite that will tell you what your actual connection speeds are.I first set up my client for a 150KB/s upload but noticed that my download speed was regularly under 100KB/s. So I dropped it over time, each time finding my max download speed going up. I finally settled on 70KB/s, which routinely gives me 250+KB/s download speeds.One thing to remember is that your download speed also depends upon how many connections you have and how fast the other people in your swarm are uploading. Many times it seems like everyone is uploading at 2KB/s or less, making downloads take days or weeks. It also depends on where you’re located; when I lived in Hawaii I usually had sub-100KB/s downloads because of latency and other network issues even though I had a 1.5MB/s broadband connection.

3. Queue your transfers. Each transfer you have affects how much total bandwidth can be dedicated to each. Your download speed is roughly proportional to your upload speed so the more transfers in progress, the less upload speed each one will have. However, as I found out, having a huge upload limit doesn’t necessarily mean you’ll maximize your download speeds. I usually have 3-4 tranfers running and queue up any others. As one download is completed, the next one in the queue is automatically started.

4. Though not directly related to your download speeds, seeding is important when your download is done. Seeding is the process of uploading your file for a while after you’ve got it. This can be done either after you’ve downloaded it or when you want to provide a file you already have. It’s recommend to continue seeding a file until you’re upload to download ratio is between 1.0 and 2.0. The ratio simply means that you’ve uploaded at least one full copy of the file so that a complete copy is now available on the network. It’s very frustrating to be downloading a file and have it get stuck at 98% because there isn’t a complete seed available.

5. One final thing to consider is consider an IP “blacklist” program that prevents certain IP addresses from being included in your connections. PeerGuardian is a well known, open-source application.