Checking whether the service is down
<pre><code>var Model = function() {

       function checkStatus(){

          JsonClient.onload = function() {

          };

          JsonClient.onerror = function(e) {

          };

       }

}
</code></pre>

<p>I know the error handler would be called when my request parameter is wrong or may be even if the service is down too. </p>

<p>But is there any way i can check my service is down at first place before sending the data.</p>
