Examples of "object dictionaries" in application protocols.

Question

I am working on an application protocol for SCADA type applications. From previous experiences with SNMP and CAN Open, I like the idea of "Object Dictionaries" or "Information Bases" (MIB) as a generic way to describe a device and the fields it sends / receives in messages.

Is there a proper name for this type of pattern?

Further to this... How common is it? What experiences have you had with this protocol construct? Other than CAN Open and SNMP, what other protocols use these techniques? Any recommendations?

Note, my use will need to scale to 8 bit mircos such as Atmel AVR's etc.

Thanks!

Answer 1

I believe OPC uses somthing like that. It has a standard interface to query the available object, if I recall correctly.

Answer 2

Maybe you can use the OpenSCADA Project (written in Java). Itself it doesn't have any implementations for 8 bit micro controllers, but there is a clear separation of the network protocol itself and the interfaces which build on it. So it is quite possible to create a implementation which speaks the default GMPP Protocol. The advantage of that would be, you could easily use the available OpenSCADA libraries and integrate it with the rest of your systems.

If you need any help, just drop a line to Juergen DOT Rose AT inavare DOT net

http://www.openscada.org/