Using HTTP Modules To Combat Leeching

The Code Project - Using HTTP Modules To Combat Leeching - ASP.NET: "The article explains how an HTTP module can be used to combat leech requests to resources on your domain through GET or POST HTTP request methods. The code snippet provided defines a class that implements the IHttpModule interface. An instance of this class will hook into the ASP.NET runtime and intercept the BeginRequest event of the HttpApplication object and determine if the requested URI came from a leech link on another website. Leech links are simply links pointing to resources on your site without your knowledge or authorization.

This technique can be used to prevent the outside world from posting links to resources on your domain without authorization to do the same. For example, if you maintain a list of sites that have been authorized to provide links to your website, then you can put into effect a selective screening routine. On the other hand, if there are domains that you do not want to be referred from, this technique will again, prove equally useful. I have not provided the code to these ends though. My intent here is to simply illustrate a basic possibility. But you could mail me if you are interested to know how to go about it, but I believe you should be able to pull it off without much ado after reading through this article."