Avoid Chocking a Web Page:

This technique is pretty much similar to Doorway page tactic. The main idea behind chocking a web page is to show a doorway page to search engine crawlers but the “Money page” (Where ads are place) to human visitors. Both pages can access with the same URL. Software identifies the crawlers and redirect them to doorway pages and when it discovers the visitors it send them to “Money Page”. ajmalseotips.blogspot.com