2 cissp ® Official Study Guide Eighth Edition

Know the common threats to physical access controls.
No matter what form of physical 
access control is used, a security guard or other monitoring system must be deployed to 
prevent abuse, masquerading, and piggybacking. Abuses of physical access control include 
propping open secured doors and bypassing locks or access controls. Masquerading is using 
someone else’s security ID to gain entry to a facility. Piggybacking is following someone 
through a secured gate or doorway without being identified or authorized personally.
Understand the need for audit trails and access logs.
Audit trails and access logs are use-
ful tools even for physical access control. They may need to be created manually by security 
guards. Or they can be generated automatically if sufficiently automated access control 
mechanisms are in place (in other words, smartcards and certain proximity readers). You 
should also consider monitoring entry points with CCTV. Through CCTV, you can com-
pare the audit trails and access logs with a visually recorded history of the events. Such 
information is critical to reconstructing the events of an intrusion, breach, or attack.
Understand the need for clean power.
Power supplied by electric companies is not always 
consistent and clean. Most electronic equipment demands clean power in order to function 
properly. Equipment damage because of power fluctuations is a common occurrence. Many 
organizations opt to manage their own power through several means. A UPS is a type of 
self-charging battery that can be used to supply consistent clean power to sensitive equip-
ment. UPSs also provide continuous power even after the primary power source fails. A 
UPS can continue to supply power for minutes or hours depending on its capacity and the 
draw by equipment.

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