Get unique id of Device

  //******************* Source: NAYCode.com
private string GetDeviceInfo()
        {
            string mac = string.Empty;
            string ip = string.Empty;

            foreach (var netInterface in NetworkInterface.GetAllNetworkInterfaces())
            {
                if (netInterface.NetworkInterfaceType == NetworkInterfaceType.Wireless80211 ||
                    netInterface.NetworkInterfaceType == NetworkInterfaceType.Ethernet)
                {
                    var address = netInterface.GetPhysicalAddress();
                    mac = BitConverter.ToString(address.GetAddressBytes());

                    IPAddress[] addresses = Dns.GetHostAddresses(Dns.GetHostName());
                    if (addresses != null && addresses[0] != null)
                    {
                        ip = addresses[0].ToString();
                        break;
                    }
                }
            }

            return mac;
        }