How to determine MAC Address of the actual physical network card — not virtual network interfaces created by VPN's (.NET C#)

Question

Background

I\'m trying to get obtain a unique identifier out of a computer and want to be able to reliably return the same MAC address each time. Trust me I have

Answer 1

 public static string GetMacAddressPhysicalNetworkInterface()
    {

        ManagementObjectSearcher searcher = new ManagementObjectSearcher
        ("Select MACAddress,PNPDeviceID FROM Win32_NetworkAdapter WHERE MACAddress IS NOT NULL AND" +
         " PNPDeviceID IS NOT NULL AND" +
         " PhysicalAdapter = true");
        ManagementObjectCollection mObject = searcher.Get();

        string macs = (from ManagementObject obj in mObject
                let pnp = obj["PNPDeviceID"].ToString()
                where !(pnp.Contains("ROOT\\"))
                //where  pnp.Contains("PCI\\")  || pnp.Contains("USB\\")
                select obj).Select(obj => obj["MACAddress"].ToString())
            .Aggregate(null, (mac, currentMac) => mac + currentMac.Replace(":", string.Empty) + ",");

        return !string.IsNullOrEmpty(macs) ? macs.Substring(0, macs.Length - 1) : macs;
    }

    public static NetworkInterface GetPhysicalNetworkInterface(string macAddressPhysicalNetworkInterface)
    {
        return NetworkInterface.GetAllNetworkInterfaces().FirstOrDefault(currentNetworkInterface => string.Equals(currentNetworkInterface.GetPhysicalAddress().ToString(), macAddressPhysicalNetworkInterface, StringComparison.CurrentCultureIgnoreCase));
    }