Re: Simple Components 4.12 with MQTT implementation released

[slos <new.stephane.los@gmail.com>]

Le vendredi 15 avril 2016 17:05:56 UTC+2, Dmitry A. Kazakov a écrit :
> On 2016-04-15 12:06, slos wrote:
> 
> > We share some of the vision.
> > "Ada for Automation" is a framework with which one can build his own
> > control application using Ada. I would not call it a middleware.
> 
> Why not?
> 
> > And MQTT or OPC UA would just connect it to some SCADA or cloud based
> > application like one using IBM BlueMix.
> 
> Neither is good for SCADA, especially regarding safety requirements and 
> performance.
> 
> >> Note that without OPC UA everything could work far better and require
> >> far less resources. E.g. having all process data the OPC cannot access
> >> because it is too slow to pace with the middleware capable to deliver
> >> data at less than 1ms rate and does not properly support
> >> push-subscriptions, does not support distributed time stamping, physical
> >> units, error states etc.
> >>
> > I agree that OPC UA does not fit where EtherCAT, Sercos III or PROFINET IRT would.
> > OPC was created for office and SCADA / GUI applications access to
> > PLC  data, not for IO processing.
> 
> Why SCADA or DB server should ever use some other middleware protocols? 
> The point is that one middleware can stretch from the ERP levels down to 
> the field. But when the middleware is OPC or MQTT you cannot not put it 
> into a device and expect that working. This is the reason we must live 
> with EtherCAT, ProfiNET down there, which are nightmare to any system 
> integrator. That defeats the very idea of a middleware.
> 
> The real advantage of Ada is that it is scalable from heavy duty to hard 
> real-time embedded. The ugly protocols like XML, HTTP, OPC etc only 
> hinder developing of safe and efficient systems.
> 
> -- 
> Regards,
> Dmitry A. Kazakov
> http://www.dmitry-kazakov.de

Standards are created for interoperability.
If you don't need interoperability, you don't need standards.
Hence you need standards since you leave in an interconnected world now.

BR,
Stéphane