Page 712 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

Security guards are often an appropriate security control when
immediate situation handling and decision making onsite is necessary.

Unfortunately, using security guards is not a perfect solution. There

are numerous disadvantages to deploying, maintaining, and relying on
security guards. Not all environments and facilities support security
guards. This may be because of actual human incompatibility or the
layout, design, location, and construction of the facility. Not all
security guards are themselves reliable. Prescreening, bonding, and

training do not guarantee that you won’t end up with an ineffective or
unreliable security guard.

Even if a guard is initially reliable, guards are subject to physical injury
and illness, take vacations, can become distracted, are vulnerable to
social engineering, and may become unemployable because of
substance abuse. In addition, security guards usually offer protection
only up to the point at which their life is endangered. Additionally,

security guards are usually unaware of the scope of the operations
within a facility and are therefore not thoroughly equipped to know
how to respond to every situation. Finally, security guards are
expensive.

Guard dogs can be an alternative to security guards. They can often be
deployed as a perimeter security control. As a detection and deterrent,
dogs are extremely effective. However, dogs are costly, require a high

level of maintenance, and impose serious insurance and liability
requirements.

Deploying Physical Access Controls

In the real world, you will deploy multiple layers of physical access

controls to manage the traffic of authorized and unauthorized
individuals within your facility. The outermost layer will be
lighting. The entire outer perimeter of your site should be clearly
lit. This enables easy identification of personnel and makes it
easier to notice intrusions and intimidate potential intruders. Just

inside the lighted area, place a fence or wall designed to prevent