April 13, 2005
Blog Comment Spam Measures
Anyone whom has used a blog for any period of time knows how irritating comment spam can be. Comment spam is yet another way (aside from email) that spammers can try to get their advertisements to you. Comment spammers use the MovableType comment feature to try to post their spam to your blog as a comment, so when others read your blog, they see the advertisements listed on the page along with your blog entry.
While it is impossible to block all spam while simultaneously leaving the comments feature open, Willamette University has taken the following measures to try to quell blog comment spam:
- We subscribe to a blacklist to block well-known spammers from posting comment spam to your blog. The blacklist is updated daily with information designed to stop top spammers from posting comments to your blog.
- By default comments are moderated, requiring the author's approval before a comment is posted to your blog. You may receive some spam here, but you can delete it before it is actually posted to your blog and viewable by the world.
- We have a hard limit on comments posted to blog.willamette.edu per-hour, so if a large volume of spam comes in all at once, it can be stopped.
- We use the "nofollow" plugin for Movable Type, which makes blog comments unrankable by search engines. Theoretically this makes blog spamming less valuable to spammers, but may not have any effect as to how much spam is received.
- We use an additional plugin called "Conversation Killer", which can be used to automatically close comments on blog entries after a specified number of days. Normally, articles are usually commented on shortly after they are written, and then comments die down. By closing comments after some number of days, you can limit the amount of spam your blog receives.
These techniques should help reduce blog comment spam, but cannot remove it entirely. There are two major things you can do to reduce the amount of spam your blog receives:
- Disable comments for your blog if you do not find them necessary. Disallowing comments completely is the only foolproof way to stop comment spam. You can disable comments for your blog inside the "Weblog Config" section of Movable Type.
- If you do allow comments, consider using the ConversationKiller plugin to close comments after some number of days. After you log into Movable Type, you should see a link to the ConversationKiller plugin toward the bottom of the page. Closing comments as soon as you can afford to reduces the window of time during which your blog can be spammed.
Doing the above listed things and moderating comments for your blogs, along with the measures the University is taking to block what spam it can, should reduce the time spent dealing with comment spam and it's consequences.
Posted by cfeskens at April 13, 2005 03:08 PM