title: How to avoid client caching with CDN
body: <p>Working on a project in AS3 I require to stream a few files for bandwidth testing purposes. The files needs to come from the CDN (the clients closest proxy) in order to make the bandwidth test reliable.</p>
  
  <p>Of course if the remote files get cached in the clients browser the bandwidth test would not be reliable.</p>
  
  <p>Usually I would add a time-stamp in the GET variables in order to trick the clients cache. But I can imagine this is a very bad practice working with a CDN.</p>
  
  <p>So my question is : </p>
  
  <p>how to force bypass the clients cache to retrieve a new version of a file without really changing the request ?</p>
  
  <p>Thanks in advance,</p>
  
  <p>T</p>
  
  <p><strong>EDIT :</strong> </p>
  
  <p>The ideal would be to send a cache-control header in URLRequest (thanks Assaf!). Unfortunately I've been trying it out for a little while and it doesn't seem to work within FlashPlayer. Even on the web, people seems to be pessimistic about the subject. </p>
  
  <p>Quick example :</p>
  
  <pre><code>var headers:Array = new Array(new URLRequestHeader("Cache-Control", "no-cache"));
  urlRequest.requestHeaders = headers;
  urlRequest.load(url);
  </code></pre>
  
  <p>Anybody ever managed to make something similar to work ?</p>