Get System's Public IP Address

getPublicIP.js

    $(document).ready(function () {
        var xmlhttp = new XMLHttpRequest();
        var url = "http://ipecho.net/plain";

        xmlhttp.onreadystatechange = function () {
            if (this.readyState == 4 && this.status == 200) {
                IP = this.responseText;
                // IP variable stores the PUBLIC IP address of the system
                //for eg 110.44.116.42
            }
        };
        xmlhttp.open("GET", url, true);
        xmlhttp.send();
    });