Monitor/capture tcp data between a server and client

[Little_Helper]

Hi

I am doing a server/client TCP connection between my laptop and another computer running the server program. With my client program I am able to send commands to the server to which it reacts. However I do not know what the commands are (I just press a button in the client GUI and the command is sent), so my initial thought was that, maybe I was able to monitor/capture the strings/bytes/integers commands, which is send over the TCP/IP. There are only these two computers on the network, so no problem in other traffic there. FYI, they are connected with a wireless peer-to-peer connection.

My problem comes from the manufature of the software making a crabby manual, so really the commands in the manual, which I was supposed to send with my own TCP vi, are just impossible to understand, and don't get me started with their support 🙂

SO, any suggestions if it is possible to capture what is sent over the TCP when I press a button in my client GUI?

[Matthew_Williams]

Wireshark, http://www.wireshark.org , will capture data off the network and sort/display/categorize.

I don't know how well it will work in a wireless environment, we usually use a wired hub (not switch).

Matt

[MikeS81]

Hi SCMAJA,

another way is to build your own TCP/IP Server with LabView and receive with it the commands send with your client program.

Mike

[Little_Helper]

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Matthew Williams wrote:
Wireshark, http://www.wireshark.org , will capture data off the network and sort/display/categorize.

I don't know how well it will work in a wireless environment, we usually use a wired hub (not switch).

Matt

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Hi Matt

I have just tried Wireshark, I get a lot of data, so I just have to use a bit of time figuring out what is what, but good program to monitor the LAN connection also wireless. I can monitor all the packages between the client and server. It looks like there is a bunch of data just from keeping the connection active, but again I have to dig a bit deeper before I can say anymore:-)

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MikeS81 wrote:

Hi SCMAJA,

another way is to build your own TCP/IP Server with LabView and receive with it the commands send with your client program.

Mike

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Hi Mike

Yeah I tried that right now using the TCP Communicator - Passive example, unfortunately the connection between the client and server is kept alive using some commands, so the only command I can get to read is the connect command, because the client then refuses the connection because there is no "right" answer/repsonse from the server 😞

edit:

I just got in touch with the support, and got some of the commands to work. I had to make some crazy command with a header first, then size and last my command, all converted from DEC to HEX.. Not easy to figure out 🙂

Message Edited by SCMAJA on 02-08-2008 04:29 PM