ASP.NET

<configuration>
  <location path="Admin">
    <system.web>
      <authorization>
        <deny users="?"/>
      </authorization>
    </system.web>
  </location>
</configuration>

<authentication mode="Forms">
  <forms name=".ASPXAUTH" loginUrl="login.aspx" timeout="20" 
  protection="All" slidingExpiration="true"  defaultUrl="/Admin/MyAdminPage.aspx"/>
</authentication>

window.onload = function(){ setTimeout('imageSwap', 6000); }
var swap = true;
function imageSwap() {
    var img = document.getElementById['imageElId'];
    if(swap) { img.src = 'newimage.jpg'; swap = false; }
    else { img.src = 'oldimage.jpg'; swap = true; }
}

badgrs wrote:

Why would you need Ajax for this

function rotateImage()
{
  var currentImage = document.getElementById('myImage').src;

  if (currentImage = 'imgage1.gif')
  {
    document.getElementById('myImage').src = 'image2.gif';
  }

  else
  {
        document.getElementById('myImage').src = 'image1.gif';
  }

  setTimeout ('rotateImage();', 6000)
}