When downloading from the Internet using the Bittorrent protocol, there are a few risks. No matter what you download, there always exists the possibility that someone will send you junk data. This can – at worst – cause your download to become corrupt, but even if it isn’t that serious, your client will generally have to download the faulty segments over, hopefully from someone who isn’t spamming the torrent.
If you’re downloading something copyrighted, there is a high probability that an anti-piracy organization may be tracking your activity, which will lead to a notice from your Internet provider, and potentially the loss of your Internet account and maybe even a lawsuit.
A blocklist – a list of IP addresses known to have displayed certain behavior that you want to block because of that behaviour – is a good way to limit, if not stop, those types of users from connecting to your client. Transmission, a popular torrent client available for Mac, Linux and Windows (via a third-party port), has long had the ability to use blocklists.
In fact, until recently, the process was as simple as clicking a checkbox to enable the feature. But with the last couple versions, the Transmission developers have removed the built-in blocklist. The feature still exists, but you have to know a bit more in order to use it. Here’s how.
The first thing we’ll want to do is open Transmission and navigate to the preferences. In Windows and Mac OS X, Transmission should be in with the rest of your applications, while in Linux it should be in your Internet or Network folder.
Once Transmission is running, navigate to the Preferences area.
Now click on the Privacy tab.
You’ll see the blocklist information, turned off by default, at the top of this tab. To enable the use of a blocklist, make sure the Enable Blocklist checkbox is ticked.
In past versions of Transmission, this was enough; you only needed to update the blocklist, and you were done. Now, however, since the built-in list has been removed, you need to find your own list. A good place to find lists of all types is the I-Blocklist lists page. I-Blocklist is a website “dedicated to the creation and distribution of IP lists for use with IP blockers such as PeerBlock, PeerGuardian, Moblock, and iplist,” and as it turns out, these lists work with Transmission. To see a full list of all the blocklists available, go to iblocklist.com and click the Lists link.
There are dozens of links available, but the one that was previously used by Transmission, the Level 1 list from Bluetack, is on this list. You can find it there, or simply copy this link:
http://list.iblocklist.com/?list=bt_level1
Now, type or paste the above link into the blocklist entry field in Transmission and click the Update button.
Transmission will download the list, parse it, and convert it into a .bin file it understands. If and when the process is complete, you’ll see this window:
Last, you’ll want to make sure the Enable Automatic Updates option is checked, so as new IP addresses are added to the list, you’ll be kept up-to-date.
And that’s it! Using a blocklist doesn’t really guarantee anything. You may still get junk uploaders sending you garbage that needs to be re-downloaded. You may still be tracked by an anti-piracy watchdog and get a letter from your ISP. But a blocklist should – at the very least – reduce this by a great deal, making your torrent downloads faster and more efficient in the process.