Initial thinking

[ferrisoxide]

I've started collecting interesting technologies: http://xpca.org/interesting_technology/

A few other that spring to mind:

* BERT: http://bert-rpc.org/
* PLCOpen (inc. TC-6): http://www.plcopen.org/

And I'm sure there's plenty more, though probably we should start off
just figuring what XPCA is about:

* What's at it's core?

I say "simplicity". Or maybe "openness". What else?

* Relationship to OPC

If it's to take the space that OPC UA doesn't touch, what things
should it be that OPC UA isn't?

* Supported protocols

I think this is where it gets started: how do we talk to an XPCA-
device? REST is one way (and nice and simple) but there are others.
What's important? AMQP? Modbus? TCP/IP? How high or low do our
protocols go?

* Architecture(s)

How strict should the XPC Architecture be? Should it define a
specification that every system has to adhere to, or should we just
have "recipes"? Or a blend?


That's just my brain dump for the moment.

-Tom

[Darren]

I've been thinking about the level that ideas like this should reside.
Is it as a middle man between the scada and device or should it be at
the device itself.

There are many protocols for communicating with devices what if there
was one standard for communicating with a device. My preferences would
be for a RESTful API over http. Devices are getting smarter and more
capable so there is no reason that devices couldn't implement a
webserver as their interface to the device. From my understanding this
is what OPC servers are, acting as a middle man to abstract over the
comms protocol. I believe there are OPC servers that are implemented
in embedded devices but I think there is a need for a simpler API and
a RESTful one at that.


Darren