TCP - how to capture output to port 1570?

[Jacques Bosch]

Hi there guys.

Hope somebody can give me a bit of direction here.

I have to write a software module to capture TCP/IP data that is output to port 1570 by a PBX. The PBX has a fixed IP address.
All I can get out of these guys is that this data is output to this port. Now, since I have 0 TCP/IP programming experience, I find my self at a bit of a loss as to where to begin. What is needed to capture this data? Do I just sit listening to this port waiting to catch data?
Perhaps somebody can point me in the right direction; what library / java api to use, where to start.
The product is the Opera 4.12e from http://www.mdsgateways.com/.

It sounds to me that it's not too complicated, if I just have a starting point.

Any help will be greatly appreciated!

Thanx much!!

J

[Stefan Wagner]

Call me weisenheimer, but you capture INPUT FROM port ..., or SEND OUTPUT TO port. Of course the output from x is the input for y...

Here is an example with a small timeout - perhaps you better wait immediately (timeout = 0 or -1, see docs).
And a bigger buffer might be good, until you know more details.

Perhaps I should know what PBX is?

import java.io.*;
import java.net.*;
// ...
DatagramSocket datagramSocket = null;
DatagramPacket datagramIn = null;
int timeout = 100;
 
byte [] inBuffer = new byte [8];
 
try
{
datagramSocket = new DatagramSocket (1570); 
datagramSocket.setSoTimeout (timeout);
}
catch (SocketException se)
{
se.printStackTrace ();
System.exit (1);
}
datagramIn  = new DatagramPacket (inBuffer, inBuffer.length);
 
try
{
datagramSocket.receive (datagramIn);
System.out.println ("received: " + (fromByteArray (inBuffer)) + "\t" );
}
catch (SocketTimeoutException ste)
{
System.err.println ("no server response before timeout: " + timeout);
}
catch (UnknownHostException uhe)
{
uhe.printStackTrace ();
}
catch (IOException ioe)
{
ioe.printStackTrace ();
}
finally
{
datagramSocket.disconnect ();
datagramSocket.close ();
}

the ...receive (...) line waits until a Datagram is received or the timeout occured.
Then the data is in raw form in the inBuffer.

Perhaps you best start first with two programs on localhost, a sender(=client) and a receiver (=server), and dump the received data to System.out.

[Jacques Bosch]

Hi Stefan.

Call me weisenheimer, but you capture INPUT FROM port ..., or SEND OUTPUT TO port. Of course the output from x is the input for y...

I do know that much.

Perhaps I should know what PBX is?

A PBX or a PABX is a switch board system. Send out data on every call that is made in the company.

Here is an example with a small timeout - perhaps you better wait immediately (timeout = 0 or -1, see docs).
And a bigger buffer might be good, until you know more details.

Because the data is sequential, DatagramSocket might not be the right choice.
I have written a working server / client with just Socket and ServerSocket.
Of course, I won't know if my server behaves like the real thing until we are able to test it on site.

Thanx much for your help.
Any further thoughts?

J