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 autolearn=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!mx02.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: IoT / IIoT stuff Date: Sat, 23 Jan 2016 09:05:35 +0100 Organization: Aioe.org NNTP Server Message-ID: References: NNTP-Posting-Host: LNA1TkTuMxfwTHzeJdi6nA.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 X-Notice: Filtered by postfilter v. 0.8.2 Xref: news.eternal-september.org comp.lang.ada:29207 Date: 2016-01-23T09:05:35+01:00 List-Id: On 2016-01-22 19:59, tmoran@acm.org wrote: >> This is not how automation applications are designed and are required to >> be, as they know exactly where devices are and which sensors and >> actuators they have. > Lots of cheap sensors and actuators implies designing for unreliable, but > multiply redundant, sets of devices. How can you build a redundant system without knowing what is there, being redundant or not? The point is that any automation system always deals with some physical real life process. The inputs and outputs are mapped onto some physical entities. A sensor is there to measure a concrete entity of the process. You can use many sensors to measure the same entity in a redundant manner or you can have subsystems dormant when some measurements are unavailable, but you always know what you measure and what you control. A sensor in a "cloud" without reference to the process at hand has no use. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de