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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
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.
RS-232
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