Question

I am using NetworkInterface.GetAllNetworkInterfaces() to take my network interfaces,

then I trying to take my MAC addreses (NetInterf[i].GetPhysicalAddress())

and it takes me my real interfaces and some trash:

[0]: ""
[1]: "00E018998877"
[2]: "001F3C0B4F5D"      
[3]: ""
[4]: "00000000000000E0"
[5]: "00000000000000E0"
[6]: "00000000000000E0"
[7]: "00000000000000E0"

[1] and [2] my real MAC adress but other is wrong,
MAC addres must have 6 bytes, isn’t?

In program I am filtering with such condition

if (NetInterf[i].GetPhysicalAddress().GetAddressBytes().Length == 6)

I’m doing right? Because I can’t find anything about it in MSDN.

Answer 1

The more clear way to get all real interfaces will be to use WMI. You can retrieve all network adapters information from the Win32_NetworkAdapter class. To determine whether the adapter is a physical or a logical adapter need to check PhysicalAdapter property. Here is example:

var scope = new ManagementScope(@"\\localhost\root\cimv2");
scope.Connect();
var query = new ObjectQuery(@"SELECT * FROM Win32_NetworkAdapter WHERE PhysicalAdapter = True");
var searcher = new ManagementObjectSearcher(scope, query);

var networkInterfaces = searcher.Get();
foreach (var networkInterface in networkInterfaces)
{
    Console.WriteLine(string.Format("{0} - {1}", networkInterface["MACAddress"], networkInterface["Name"]));
}

Using NetworkInterface.GetAllNetworkInterfaces() you can’t determine that for sure.