title: Asking browsers to cache our images (ASP.NET/IIS)
body: <p>I just ran <a href="https://developers.google.com/speed/pagespeed/insights" rel="noreferrer">Google's Page Speed</a> application against our site and one of the recommendations was to <strong>Leverage browser caching</strong>. Expanding this revealed the following:</p>
  
  <blockquote>
    <p><em>The following cacheable resources have
    a short freshness lifetime:
    Specify an expiration at least one week in 
    the future for the following resources:</em></p>
    
    <p><code>&lt;</code>a long list of images <code>&gt;</code><br>
    <code>&lt;</code>some javascript files <code>&gt;</code></p>
  </blockquote>
  
  <p>How do I go about lengthening the "freshness lifetime" of particular images?</p>
  
  <p>It's an <strong>ASP.NET</strong> project running on <strong>IIS7.5</strong></p>