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<== Date ==> | <== Thread ==> |
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Subject: | Re: Caget packet structure |
From: | Mark Engbretson <[email protected]> |
To: | Stephen Molloy <[email protected]> |
Cc: | "[email protected]" <[email protected]> |
Date: | Sat, 18 Jun 2016 14:56:29 -0500 |
Fastest way is to turn on a packet sniffer such as wireshark, look at the actual communication, and then see how easy or hard it is reproduce with your hardware. If your micro controller is doing the caget equivalent, you should know that this is generally a multi stage operation. You send out a search request for a PV, the IOC or gateway hosting it responds with a message that says that it has it. You then authenticate to threat system with what host and user you are, and then you actually make the request asking for the data either as the PV native type, or a easier to deal with representation. If your going to be doing this as more than a one-shot request, you also have to be aware that there is a "are you still alive" request that generally happens in the background. And may want the request to actually be a callback so that you get a data packet whenever the requested data changes. Why using wireshark is the way to go, since it will show everything that is happening. Hi,
I'd like to send and receive a caget command over the network using a microcontroller. Could someone let me know the structure of the packet that I need to send to the network? And the structure of the packet that will come back? Thanks, Steve |