What's the best way to ping many network devices in parallel?

Question

I poll a lot of devices in network (more than 300) by iterative ping.

The program polls the devices sequentially, so it\'s slow. I\'d like to enhance the speed of pollin

Answer 1

Direct ICMP access is deprecated on windows. Direct access to the ICMP protocol on Windows is controlled. Due to malicious use of ICMP/ping/traceroute style raw sockets, I believe that on some versions of Windows you will need to use Windows own api. Windows XP, Vista, and Windows 7, in particular, don't let user programs access raw sockets.

I have used the canned-functionality in ICMP.dll, which is what some Delphi ping components do, but a comment below alerted me to the fact that this is considered "using an undocumented API interface".

Here's a sample of the main delphi ping component call itself:

function TICMP.ping: pIcmpEchoReply;
{var  }
begin
  // Get/Set address to ping
  if ResolveAddress = True then begin
    // Send packet and block till timeout or response
    _NPkts := _IcmpSendEcho(_hICMP, _Address,
                            _pEchoRequestData, _EchoRequestSize,
                            @_IPOptions,
                            _pIPEchoReply, _EchoReplySize,
                           _TimeOut);
    if _NPkts = 0 then begin
      result := nil;
      status := CICMP_NO_RESPONSE;
    end else begin
      result := _pIPEchoReply;
    end;
  end else begin
    status := CICMP_RESOLVE_ERROR;
    result := nil;
  end;
end;

I believe that most modern Ping component implementations are going to be based on a similar bit of code to the one above, and I have used it to run this ping operation in a background thread, without any probems. (Demo program included in link below).

Full sample source code for the ICMP.DLL based demo is here.

UPDATE A more modern IPHLPAPI.DLL sample is found at About.com here.