From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM autolearn=unavailable autolearn_force=no version=3.4.4 X-Received: by 10.129.154.88 with SMTP id r85mr12200568ywg.11.1460714800259; Fri, 15 Apr 2016 03:06:40 -0700 (PDT) X-Received: by 10.157.11.1 with SMTP id a1mr223122ota.6.1460714800193; Fri, 15 Apr 2016 03:06:40 -0700 (PDT) Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!mx02.eternal-september.org!feeder.eternal-september.org!usenet.blueworldhosting.com!feeder01.blueworldhosting.com!border2.nntp.dca1.giganews.com!nntp.giganews.com!10no3780364qgg.1!news-out.google.com!u9ni68igk.0!nntp.google.com!g8no1445195igr.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Fri, 15 Apr 2016 03:06:39 -0700 (PDT) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=193.251.73.50; posting-account=O3LyFwoAAACc1uh60ZcOUmAGdDmGsEcV NNTP-Posting-Host: 193.251.73.50 References: <6d3b7ac5-8fc6-406c-8aac-947d25a78249@googlegroups.com> User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: Subject: Re: Simple Components 4.12 with MQTT implementation released From: slos Injection-Date: Fri, 15 Apr 2016 10:06:40 +0000 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Xref: news.eternal-september.org comp.lang.ada:30121 Date: 2016-04-15T03:06:39-07:00 List-Id: Le vendredi 15 avril 2016 10:01:31 UTC+2, Dmitry A. Kazakov a =E9crit=A0: > On 14/04/2016 23:30, slos wrote: >=20 > > Be prepared to ear about it soon. > > Just google for "industry 4.0 opc ua" >=20 > Well, actually I am involved in an Industry 4.0 project: >=20 > http://www.secureplugandwork.de/servlet/is/10291/ >=20 Good to know ! Thank you for the link. > We indeed use OPC UA in this project. But OPC UA is unsuitable for field= =20 > automation, basically, for any work associated with data acquisition and= =20 > control. Of course but like nobody, I don't intend to use it in this case. There are already plenty of industrial protocols fitting here. "Ada for Automation" is using libmodbus for Modbus RTU and TCP communicatio= ns and Hilscher boards for all major field buses. > Therefore the architecture is that the OPC UA is only a gateway=20 > to the applications. All actual the work is done by the middleware=20 > developed by cbb software GmbH running on the system nodes (ARM boards).= =20 > The middleware feeds an UPC UA server which the gateway's OPC UA client= =20 > accesses. BTW, the middleware is 100% Ada and 0% OPC. We share some of the vision. "Ada for Automation" is a framework with which one can build his own contro= l application using Ada. I would not call it a middleware. And MQTT or OPC UA would just connect it to some SCADA or cloud based appli= cation like one using IBM BlueMix. > Note that without OPC UA everything could work far better and require=20 > far less resources. E.g. having all process data the OPC cannot access=20 > because it is too slow to pace with the middleware capable to deliver=20 > data at less than 1ms rate and does not properly support=20 > push-subscriptions, does not support distributed time stamping, physical= =20 > units, error states etc. >=20 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. > That was the reason why it was decided that the OPC UA gateway would not= =20 > deal with process data at all. It is used only for configuration and=20 > possibly for history process data. >=20 > In short, there are serious multiple reasons why OPC UA cannot be used=20 > in the field, regardless how strong the push for it is. >=20 > --=20 > Regards, > Dmitry A. Kazakov > http://www.dmitry-kazakov.de St=E9phane