How to Use the rel="nofollow" Attribute to Help Combat Weblog Comment Spam
by Geethalakshmi[ Edit ] 2010-03-27 21:30:15
How to Use the rel="nofollow" Attribute to Help Combat Weblog Comment Spam
The Yahoo! Slurp web crawler obeys the rel="nofollow" attribute for links. Web publishers and blog owners can apply a rel="nofollow" attribute to any hyperlink on their page to indicate that the link may not be an approved or trusted link.
Note: Yahoo! Slurp may use a "nofollow" link for discovering content, but the link will not be considered an "approved" link for consideration when ranking the target page.
This attribute works to reduce the benefits of comment abuse. For instance, websites with public comment areas can apply a "nofollow" attribute to publicly entered links to help fight comment spam.
Applying the rel="nofollow" Attribute:
Example:
<a href="http://spammer.example.com/">buy now</a>
changes to:
<a href="http://spammer.example.com/ rel=nofollow">buy now</a>
The rel="nofollow" attribute applies to single HTML tags. To prevent Yahoo! Slurp from following all links on a page, place a robots "nofollow" metatag in the <HEAD> section of the page or use the X-Robots-Tag as shown:
Applying the "nofollow" metatag:
Example:
<meta name="robots" content="index,nofollow">
Applying the "nofollow" Directive:
Configure your web server to place the following directive in the HTTP header used to serve the page:
X-Robots-Tag: nofollow
