October 2018 AST 'ASTORS' Finalist Edition Oct 2018 AST Magazine Final (10.16.18) | Page 62

difficult
to monitor lo-
Volume 27
cations due to limited
range, they run in paral-
lel, or in those environ-
ments can be spoofed or
defeated.
Industry-standard systems
employ low-voltage, nor-
mally open or normally
closed circuits that acti-
vate a relay when there is a
change in some state of the
sensor.
The most common are magnetic reed
switches used to secure doors and windows.
September 2018 Edition
ble to monitor until now.
Using fiber optics, we can now
use light to detect the states of
switches.
These sensors need to be directly connect-
ed by wires to the security relay panel and
can require a stringent maintenance pro-
Optical fiber can be used to transmit
gram.
and receive signals over miles and is
The systems themselves are known and completely passive.
proven.
There are companies in every city that
can install and maintain the systems
and security professionals at secure
locations are familiar with their opera-
tion.
It does not require any electricity at the sens-
ing location and is immune to EMI and RFI.
It is not detectable using a metal detector.
Fiber systems can use long serial runs
of many sensors over a single optical
A new generation of security sys- fiber each of which have a unique opti-
cal signature that cannot be spoofed or
tems is now available that can be
bypassed.
used over long distances to secure
locations that have not been possi- Current optically-based systems
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