Google aims to outsmart search tricksters

update Google will introduce new technology controls to thwart people using blogs to manipulate rankings in its search results.

Otherwise known as “link” or “comment spam,” the ruse is as old as Web marketing. Such Web site promoters use the comment form on forums, blogs or any Web page to place or gain a link pointing back to their own Web site. And because Google and other search engines tabulate search results in part by a Web page’s link popularity with other sites, the trick can boost a site’s ranking–and more importantly, traffic. It can also produce irrelevant search results.

In the age of blogging, the problem has grown acute because publishers have little recourse to stop outsiders from littering their comment forms with bogus links, short of shutting them down or inserting password protections.

Late Tuesday, Mountain View, Calif.-based Google plans to detail in its own blog a new tactic for blocking link spammers, according to a company representative.

Danny Sullivan, a search engine expert, said that Google plans to give publishers a new control, or tag, that they can insert onto a Web page to indicate that comments or links are not their own or of lesser value to the search engine. Called a “no follow” tag, the control when placed before pages of blog comments will signal to Google as it indexes the Web that the pages are to be overlooked. That will render comment spam ineffectual.

“The tag provides you a way to flag links that are basically not yours. The reason why that’s helpful is because they won’t count those links,” said Sullivan, who added that the problem won’t go away entirely. “It makes the idea of comment spamming less attractive.”

Sullivan said that the indexing tag will be the first innovation in almost 10 years for publishers. The last was a tag to avoid being indexed entirely by the search engines. “It’s nice to see the search engines give Web authors a new tool to control how we’re indexed,” he said.

Other blog companies are onboard, too. Six Apart, which operates professional and individual blog-publishing services, said Tuesday that it will immediately adopt the tagging standard for its roughly 6.5 million blogs. That means that people who publish using Six Apart’s Typepad will automatically have tags on their blogs delineating between content they publish and that of third parties who use a comment form. Professionals using Six Apart’s Moveable Type application will be newly equipped with a plug-in to do the same.

“We’re interested in deploying this tool so that all the search engines, whether it’s Google, Yahoo or MSN, can properly distinguish content published by the author from content from commentors,” said Anil Dash, vice president of the professional network at Six Apart.

Rumors of the new controls have been circulating in recent days on several blogs including Micro Persuasion and Scobleizer. The Scobleizer blog is penned by Microsoft employee Robert Scoble.

Steve Rubel, a blog evangelist and vice president of CooperKatz, a public relations firm, said the move is significant because blogs factor heavily into search engine rankings and that makes them a target for spammers. The “no follow” tag should mitigate the problem, he said.

“It’s a welcome move that the blogsphere will cheer,” Rubel said.