No tcp connection in of tcp server

I am trying to make labview program to replace a java program on a pc(192.168.1.88).
The first step is the program will start a tcp server, then a client(192.168.1.44) will connect in. The java program works fine, but my program all the time waiting and no connection in.
I tried wireshark. When java program receive the connection, it only give 4 lines, my program got many lines and no connection as attached.
Any suggestion, thank.
Solved!
Go to Solution.
Attachments:
ss.png ‏134 KB

Showing some relevant section of the Java program source would probably help. Or from the client program. There might be a number of things. As to the wireshark log, all those entries in there are from many things, which could be in some ways related to LabVIEW but none but one line are related to your actual problem. And looking at your example you posted later, you should not let the listen socket get closed right away. Think dataflow!Another recommendation since you are not using the address information anyhow, set the resolve remote address to false. It could add a huge delay accepting the incoming connection request, since it will cause a name resolution request on your network which will possibly timeout because of no DNS server being available, and even if you have a DNS server it is not clear if it will contain a name record for that device.
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

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TCP server implementation: thead issue

Hi,
I'm not actually doing a TCP server, but I need to implement a similar threading model
in my app, so this will serve as a good example. I have done a TCP server few times
with different programming languages and here's a pseudocode how I do it
do
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while(running)
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I can think of a solution that could process the clients, if the number of clients is known
at development time.
Can I somehow create threads with LabView at run-time?
This whole thread issue in LabView is quite confusing to me, so if someone knows a good
solution to that TCP server problem, I would really appreciate it. I think that would help me
understand this matter.
Thanks.

The LabVIEW terms you need to understand are VI Server and reentrant execution. There are some great TCP examples that ship with LabVIEW that should help you along...
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Message Edited by Phillip Brooks on 07-25-2007 08:57 AM
Now is the right time to use %^<%Y-%m-%dT%H:%M:%S%3uZ>T
If you don't hate time zones, you're not a real programmer.
"You are what you don't automate"
Inplaceness is synonymous with insidiousness

TCP SERVER labview CLIENT not labview

Hi
I maked a little TCP server with labview like the example with little modification (I read data from serial port...)
If I use client build with labview I launche client and I read every time data until clint disconnect, if I use a client not build in labview I read only one time not in continue (server doens't write after the first time also if client is connect)
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elisa
Attachments:
Multiple Connections - Servercon Seriale.vi ‏161 KB

HI,
Can you explain in detail how you modify your program.
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Hopefully, get a reply from you.
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Hi,
I have a high visibility application that has a bug in it that I'd like some
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The app is on the International Space Station. I have a LV executable on a
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=================================
My quandary is that in LV, I can't see what's going on in the TCP Server or
TCP Client vis.
Any suggestions will be appreciated.
JIM
Solved!
Go to Solution.

I would look at configuring the Nagle Algorithm and/or Delayed ACK options on your remote and earth-bound stations.
Do LabVIEW TCP Functions Use the Nagle Algorithm?
TCP Performance problems caused by interaction between Nagle's Algorithm and Delayed ACK
From wikipedia:
Applications such as networked multiplayer video games expect that actions in the game are sent immediately, while the algorithm purposefully delays transmission, increasing bandwidth at the expense of latency. For this reason applications with low-bandwidth time-sensitive transmissions typically use TCP_NODELAY to bypass the Nagle delay.
Now is the right time to use %^<%Y-%m-%dT%H:%M:%S%3uZ>T
If you don't hate time zones, you're not a real programmer.
"You are what you don't automate"
Inplaceness is synonymous with insidiousness

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Thanks for your help.

The best example I have found is this one
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