Script used for the IPv6 Observatory study to monitor IPv6 on web clients.

webclient.js

/*
*   IPv6 observatory - Monitoring the worldwide deployment of IPv6
*   http://v6demon.ipv6observatory.eu - http://www.ipv6observatory.eu
*
*   This script aims at measuring the actual deployemnt of IPv6 and is placed on various
*   websites to check the IPv6 connectivity of web browsers.
*
*   How its works: the script tries to access a remote image through 3 distincts URLs (IPv4 only,
*   IPv6 only and IPv4/IPv6). The script is executed only once daily for each web client on a given website.
*
*   For any request, please contact the IPv6 Observatory team through the contact
*   form on the study website: http://www.ipv6observatory.eu/contact/
*
*   (c) inno TSD - 2013 - http://www.inno-group.com/ - http://www.ipv6observatory.eu/
*
*/

var IPv6Obs = {
  uuid: function() {
		// http://stackoverflow.com/a/2117523/243958
		return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
		    var r = Math.random()*16|0, v = c == 'x' ? r : (r&0x3|0x8);
		    return v.toString(16);
		});
	},
	imageUrl: function(prefix, uuid) {
		// prefix: v4|v6|v4-v6
		return "http://demon-" + prefix + ".ipv6observatory.eu/" + (new Date).getTime() + "/1x1.gif?uuid=" + uuid + "&sid=" + "ABCDEFGH" ;
	},
	performTest: function(url) {
		var img = new Image();
		img.src = url;
	},
	setCookie: function() {
		var date = new Date();
		date.setTime(date.getTime()+(24*60*60*1000));
		var expires = "; expires="+date.toGMTString();
		document.cookie = "ipv6obsv8=1"+expires+"; path=/";
	},
	checkCookie: function() {
		var cookies = document.cookie.split(';');
		for(var i=0;i < cookies.length;i++) {
			var c = cookies[i];
			while (c.charAt(0)==' ') c = c.substring(1,c.length);
			if (c.indexOf("ipv6obsv8=") == 0) return true;
		}
		return false;
	},
	start: function() {
		if (IPv6Obs.checkCookie() == false) {
			IPv6Obs.setCookie();
			uuid = IPv6Obs.uuid();
			tests = ["v4", "v6", "v4-v6"];
			for (var i=0;i<tests.length;i++) {
				IPv6Obs.performTest(IPv6Obs.imageUrl(tests[i], uuid));
			}
		}
	}
}

IPv6Obs.start();