Last year I struggled against the comment spammers, deleting dozens of bogus comments each day. I tried various techniques and finally settled on using a captcha — a small graphic with broken up text which a commenter had to see and type in before the comment would be accepted.
This, of course, is inaccessible for people who don’t see graphics, but I also provided a link to email me directly so no legitimate comments should be blocked. This reduced the comment spam to nil, but although various comments have arrived from real people and so the system was working for at least some, yesterday I was contacted by someone who couldn’t successfully leave a comment.
I turned off the captcha and this morning have approved one legitimate comment and deleted 96 bogus spams.
So I’m thrilled to read this:
Google is implementing a new tactic for blocking “link spammers” — people who use the comment form on Web forums or blogs to place a link pointing back to their own Web site. The strategy is used to trick Google’s PageRank technology into boosting a Web site’s ranking in its results. The problem has become particularly rampant in the age of blogging, when publishers have little recourse to stop outsiders from littering their comment forms with bogus links. Google’s answer, says search expert Danny Sullivan, is to give publishers a “no follow” tag that they can insert on a Web page to indicate that comments or links are not their own and signal Google as it indexes the Web that the pages are to be overlooked. [Via NewsScan Daily.]
And it looks as though I’d better turn the captcha back on until I can troubleshoot why my correspondent had problems.