Comment & referer spam and server loads

One of my servers suffers from referer spam, sometimes it can seem like a denial of service attack, though I have a banned list and send back 403s.

Traffic has risen from last year, as it has every year, and I see that other eCommerce sites are also complaining, as they do every year, but the comment spam that Six Apart are seeing is near denial of service, as they do builds whether they block the spam or not (they're fixing this bug at the moment, but older installations are thusly dangerous for other sites on the same machine as the older MT installation—update people!) In a discussion on the issue I found one possible solution that will be just a part of the arms race, but demonstrate the problem: "...and the spammers will eventually figure out what an appropriate delay before each attempt is, but it should prevent massive server loads of 10000 comments within a minute, right?"

Now, Six Apart are working on a way of solving the problem not just for themselves, but for all in the weblogging world.

Jay Allen who created the MT BlackList and now works for Six Apart, writes: "...solving the comment spam problem once and for all and making it a non-issue, not just for us in the Movable Type/TypePad world, but also for all weblogs regardless of publishing tool. Our preference is towards solutions that scale to the entire weblog medium..."