Industrial Communications Handbook August 2016

8.1 Concluding remarks This edition of the Industrial Communications Hand- book has deviated from those in the past by not specifi- cally focusing on the nitty-gritty of specific hardware, or protocols. The actual nitty-gritty information can very often be found: [1, 2, 3] are excellent reference works, with [1] still being the best overview of RS-232 I have ever seen. Remember that the original RS-232 specification was for a 25-pin connector. This implies 2 25 different combinations!! They didn’t sell ‘patch-boxes’ for noth- ing! Remember too, that although the pared-down 9-pin connector arrived later, the combinations remained the same! At my University, a new-fangled all-singing, all-danc- ing printing ‘solution’ has been rolled out. In theory, I can sit in my office, hit the print button, walk to any printing device anywhere on campus, swipe my card, and hey-presto, out pops my print job. (Ignoring for the moment that the print job could be my exam, and that the card could have been suitably purloined …) But a closer inspection of this marvellous, brand-new distributed system reveals (Dramatic Drum Roll): Yes, it’s Ethernet as well, but the control bit contains the first 9-pin DIN I have seen in years. So someone, some- where, very recently consulted[1], probably via Profes- sor Google. But what Professor Google will not tell you is really, really why you ought in this day and age to have consid- ered using a USB port rather than an RS-232 port. Pro- fessor Google is not good at giving years worth of ‘No, don’t do it that way: this way is better’ (for the following 12 reasons …) Professor Google is particularly not good at ‘In myyyyy dayyyyy’, whereas I excel there. So what this incarnation of the Handbook attempts to do is give an overview of some of the Why’s. The handbook, together with its predecessors, also contains a treasure trove of contacts: the first-port-of-call that make up the fine folk that advertise in these pages. Stop that hysterical, cynical laughter: you know its true! If the handbook prevents you from bolting an omni- directional antenna on the side of a metal cabinet; if you RS-232

have a good idea of how high to mount your antenna; if you understand that you are employing wireless not just because its new; if you have a good argument for why a Secure Access Management system, or a basic VPN is required; if you have a considered argument for or against Proprietary/Open; if you understand that the S in SNMP is actually a C, then the handbook has done its job. 8.2 References [1] Mick Crabtree (Ed. Alan Clark). Mick Crabtree’s Industrial Communications Handbook. Crown Publications, second edition, 2005. [2] Mick Crabtree (Ed. Alan Clark). Mick Crabtree’s Industrial Communications Handbook. Crown Publications, third edition, 2008. [3] Mick Crabtree (Ed. Karen Grant). Industrial Com- munications Handbook. Crown Publications, fourth edition, 2013. [4] Karl Weber. Time sensitive networking: Deep im- pact or mission impossible? PC Control, 2015. Beckhoff Automation. [5] Frank Hakemeyer. White paper: Trusted wireless 2.0—basics and practical applications. Phoenix Contact, 2013. Phoenix Contact. [6] Tim Craven. Data acquisition from remote sites re- quires data security. Web: www.h3isquared.com. [7] Anders Hansson. Industrial network market shares 2016 according to hms. HMS, 2015. www.idx.co.za. [8] IEEE 802.3. Ethernet standard. [9] IEEE 802.11. Wireless Local Area Network stan- dard. [10] IEEE 802.11a,b,g,n. Versions of WLAN standard. [11] IEEE 802.1X. Port-based Network Access Control.

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industrial communications handbook 2016