How can I monitor active computers on my network in ASP.NET

// addressToPing can be an IPaddress or host name.
// returns a boolean indicating successful ping
public static bool PingComputer (string[] addressToPing)
{
    Ping pingSender = new Ping ();
    PingOptions options = new PingOptions ();

    // Use the default Ttl value which is 128,
    // but change the fragmentation behavior.
    options.DontFragment = true;

    // Create a buffer of 32 bytes of data to be transmitted.
    string data = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
    byte[] buffer = Encoding.ASCII.GetBytes (data);
    int timeout = 120;
    PingReply reply = pingSender.Send (args[0], timeout, buffer, options);
    return reply.Status == IPStatus.Success;
}