If you have a discussion forum or other site that requires visitors to log in with a username and password, there are a few steps you need to follow if you want to put ads on it. To authorize Google AdSense’s engine to scan and archive the main keywords of the page or pages in question, you cannot have AdSense on private, protected or limited access.

The Google AdSense system will allow you to sign up for AdSense for protected pages by going to https://www.google.com/adsense/list-auth, or you can navigate there once you’ve logged in to your AdSense account.

Google states “Use this section to allow the AdSense crawler to access pages that are behind a login. Our crawler will access these pages only to determine content for ad targeting purposes and will fully comply with Google’s privacy policy.”

Google suggests that you follow three simple steps to get things set up properly:

1. Create an authentication rule: Indicate an authentication URL and a set of parameters that will allow Google’s web crawlers to access your content.
2. Confirm you’re the owner of the site using Google Webmaster Tools by uploading a file to it or changing the META tag of a file.
   
   
3. After your authentication rule is verified, you should notice better ad targeting on your pages. You can ensure the status of your authentication rules at any time.

This feature, in all likelihood, won’t impact too many bloggers, but membership sites like newspapers and forums that require registration will find it necessary.