Page 711 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

installed base at a fixed time or an alert. They are often disguised as
planters or other architectural elements.

Lighting
Lighting is a commonly used form of perimeter security control. The

primary purpose of lighting is to discourage casual intruders,
trespassers, prowlers, or would-be thieves who would rather perform
their misdeeds in the dark. However, lighting is not a strong deterrent.
It should not be used as the primary or sole protection mechanism
except in areas with a low threat level.

Lighting should not illuminate the positions of guards, dogs, patrol

posts, or other similar security elements. It should be combined with
guards, dogs, CCTV, or some other form of intrusion detection or
surveillance mechanism. Lighting must not cause a nuisance or
problem for nearby residents, roads, railways, airports, and so on. It
should also never cause glare or reflective distraction to guards, dogs,
and monitoring equipment, which could otherwise aid attackers

during break-in attempts.

It is generally accepted as a de facto standard that lighting used for
perimeter protection should illuminate critical areas with 2 foot-
candles of power. Another common issue for the use of lighting is the
placement of the lights. Standards seem to indicate that light poles
should be placed the same distance apart as the diameter of the
illuminated area created by illumination elements. Thus, if a lighted

area is 40 feet in diameter, poles should be 40 feet apart.

Security Guards and Dogs

All physical security controls, whether static deterrents or active
detection and surveillance mechanisms, ultimately rely on personnel
to intervene and stop actual intrusions and attacks. Security guards
exist to fulfill this need. Guards can be posted around a perimeter or
inside to monitor access points or watch detection and surveillance

monitors. The real benefit of guards is that they are able to adapt and
react to various conditions or situations. Guards can learn and
recognize attack and intrusion activities and patterns, can adjust to a
changing environment, and can make decisions and judgment calls.