Identifying active network interface

Question

In a .NET application, how can I identify which network interface is used to communicate to a given IP address?

I am running on workstations with multiple network in

Answer 1

The info you are after will be in WMI.

This example using WMI may get you most of the way:

using System.Management;
string query = "SELECT * FROM Win32_NetworkAdapterConfiguration";
ManagementObjectSearcher moSearch = new ManagementObjectSearcher(query);
ManagementObjectCollection moCollection = moSearch.Get();// Every record in this collection is a network interface
foreach (ManagementObject mo in moCollection)
{    
    // Do what you need to here....
}

The Win32_NetworkAdapterConfiguration class will give you info about the configuration of your adapters e.g. ip addresses etc.

You can also query the Win32_NetworkAdapter class to find out 'static'about each adapter (max speed, manufacturer etc)