$(document).ready(function () {

    // Need to use post here rather than get because of IE caching issues.

    setInterval(function () {
        //$.post('/services/SessionPing.ashx', popAlert());
        $.post('/services/SessionPing.ashx');
    }, 180000); // 3 minutes

    function popAlert() {
        alert('Pinged!!');
    };
});