title: How to disable proxy server cache?
body: <p>Our customer used proxy to visit our service like this:</p>
  
  <pre><code>Browser &lt;--&gt; Proxy Server &lt;--&gt; Our Service
  </code></pre>
  
  <p>The proxy server was build by the customers themselves and will cache our http content(html, ActiveX control etc.). When we update the content, the customer's browser gets the old version from proxy server until the proxy server cache the newer version. The cache strategy is not controllable by us. So I want to ask are there any technologies to solve this problem? Thanks in advance.</p>