IIS6 - How to make temporary URL for AVI files (URLRewriting)?

 Hello.
I need to make temporary URLs for video files in IIS6 .
For example, we have file /videos/movie1.avi, to user we get this link: /DownloadFile.ashx?id=HDG34F34.
User must have the opportunity to multithread downloading.
How can I make it? I tried to make something like this:
 
public class DownloadFile : IHttpHandler {

public void ProcessRequest (HttpContext context) {
context.RewritePath("etp.avi");
}
 
But it's not working.
Thank You!

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