How the heck does datasocket work?

[grubworm]

I've been playing with the example vis DSReader & DSWriter, and reading docs all weekend.  The only way DSreader finds the data from the DSWriter (on another machine on the network) is if I give the reader the IP of the writer machine.  dstp//localhost/wave works when both apps are on the same machine but there's no network traffic at all according to ethereal whether the apps are on the same machine or not.  I thought, from what I read, was that any machne could find the data through the URL, but no.  I want multiple machines to broadcast and receive and all share the data.  The docs say this will work but I really can't see how from the examples.  I have been using the UDP functions for years with no problems but I can't make this work even per the documentation.   What am I missing?  Love Labview, not happy with this.

Thanks, 

Andy Bradley

EBC Electronics Corp.

[Norbert_B]

Andy,

communicating locally using TCP or UDP do not create networktraffic. This is because the data is never really sent out in the network. Only the IO buffers are used. So the connection should show up if you use something like a network sniffer. Even the DOS-prompt command netstat shows the datasocket-connection on port 3015 (dstp).

So the only thing you have to make sure if using dstp in a network (so not only local) is that the dstp-port (3015 by default) is not blocked by any firewall or used by another application.

hope this helps,

Norbert 

[nathand]

When you say "give the reader the IP of the writer" do you mean you're inserting the IP address into the URL, ie dtsp://10.0.0.2/wave, rather than using a machine name?  If that works then you aren't having problems with a firewall.  When you aren't using the IP, what machine name are you using in the URL?  Do you have a DNS entry (network-accessible machine name) for your writer so that your reader can find it by name rather than IP address?  Of course, if your reader and writer are on different machines and you use "localhost" it won't work - localhost always refers to the local computer.

[Claire_Reid]

Hey,

Have you taken a look at the DataSocket Tutorial on NI.com?

Please let me know if this helps!

[Claire_Reid]

Hi.

Just checking back to see how things are going...any update?