public static function guessIpAddress()
	{
		foreach (array('HTTP_CLIENT_IP', 'HTTP_X_FORWARDED_FOR', 'HTTP_X_FORWARDED', 'HTTP_X_CLUSTER_CLIENT_IP', 'HTTP_FORWARDED_FOR', 'HTTP_FORWARDED', 'REMOTE_ADDR') as $key)
		{
			if (array_key_exists($key, $_SERVER) === true)
			{
				foreach (explode(',', $_SERVER[$key]) as $ipAddress)
				{
					$ipAddress = trim($ipAddress);

					if (filter_var($ipAddress, FILTER_VALIDATE_IP, FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE) !== false)
					{
						return $ipAddress;
					}
				}
			}
		}
	}