CISSP Flashcards: Physical Security, Environmental Controls, Fire Suppression, Access

Physical access controls restrict entry to facilities and sensitive areas. Deterrent controls discourage attempts and include fences, lighting, signs, and security cameras. Preventive controls stop unauthorized access and include locks, mantraps or security vestibules, turnstiles, and biometric readers. Detective controls identify unauthorized access and include motion sensors, security cameras, intrusion alarms, and security guard patrols. A mantrap or security vestibule uses two interlocking doors where the first must close before the second opens, preventing tailgating.

Fire classes determine the appropriate suppression agent. Class A fires involve ordinary combustibles like wood and paper, suppressed by water. Class B fires involve flammable liquids and gases, suppressed by carbon dioxide, dry chemical, or foam. Class C fires involve energized electrical equipment, suppressed by carbon dioxide or clean agents like FM-200 that do not conduct electricity. Class D fires involve combustible metals, suppressed by dry powder agents specific to the metal. Class K fires involve cooking oils, suppressed by wet chemical agents.

Data center environmental controls include temperature management maintaining 64 to 81 degrees Fahrenheit with hot and cold aisle containment, humidity control between 40 and 60 percent relative humidity to prevent static discharge and condensation, uninterruptible power supply systems providing battery backup during short outages, generators for extended power failures, power conditioning to protect against surges and sags, water detection sensors under raised floors and near cooling systems, and positive air pressure to prevent contaminants from entering.

Tailgating, also called piggybacking, occurs when an unauthorized person follows an authorized person through a secured door or entry point without presenting their own credentials. It exploits social courtesy where people hold doors open for others. Prevention measures include mantraps or security vestibules that allow only one person through at a time, turnstiles, anti-passback systems that prevent a credential from being used twice to enter without an intervening exit, security awareness training teaching employees not to hold doors and to challenge unknown individuals, and security gu

An uninterruptible power supply, or UPS, provides immediate battery backup power when utility power fails, covering the gap of seconds to minutes until a generator starts or power returns. It also conditions power to protect against surges, sags, and electrical noise. A generator provides longer-term backup power by converting fuel into electricity, but requires 10 to 30 seconds to start and reach full capacity.

Crime Prevention Through Environmental Design, or CPTED, is a set of architectural and landscaping principles that reduce crime opportunities through design rather than hardware. Key strategies include natural surveillance using clear sightlines, windows, and lighting so potential criminals feel observed; natural access control using pathways, landscaping, and terrain to guide legitimate traffic and discourage unauthorized entry; territorial reinforcement using fences, signage, and maintenance to establish clear ownership; and activity support placing legitimate activities in areas that n