// Stampa la disponibilità della rete
bool network = NetworkInterface.GetIsNetworkAvailable();
Console.WriteLine("IsNetworkAvailable: {0}", network);

// Stampa il MAC della scheda di rete
foreach (NetworkInterface networkInterface in
NetworkInterface.GetAllNetworkInterfaces())
{
  PhysicalAddress pa = networkInterface.GetPhysicalAddress();
  Console.WriteLine("MAC: {0}", pa);

  IPInterfaceProperties ipInterface = networkInterface.GetIPProperties();
  // Stampa gli IPv4
  foreach (UnicastIPAddressInformation ip in ipInterface.UnicastAddresses)
    if (ip.Address.AddressFamily == AddressFamily.InterNetwork)
      Console.WriteLine("IP: {0}", ip.Address);
}

// Intercetta il cambio di disponibilità della rete
NetworkChange.NetworkAvailabilityChanged += new
NetworkAvailabilityChangedEventHandler(NetworkChange_NetworkAvailabilityChan
ged);
// Intercetta il cambio di indirizzo
NetworkChange.NetworkAddressChanged += new
NetworkAddressChangedEventHandler(NetworkChange_NetworkAddressChanged);
static void NetworkChange_NetworkAddressChanged(object sender, EventArgs e)
{
  Console.WriteLine("Address changed");
}

static void NetworkChange_NetworkAvailabilityChanged(object sender,
NetworkAvailabilityEventArgs e)
{
  Console.WriteLine("Available: {0}", e.IsAvailable);
}