Provide an example of a physical perimeter control used to protect assets and people.

• A. Biometric access at interior doors
• B. Fences, gates, bollards
• C. Email security
• D. Firewall rule set

Answer: (B)

Physical perimeter controls are barriers that define and protect the outer boundary of an area, deter entry, and slow down or deny unauthorized access before anyone reaches people or assets inside. Fences, gates, and bollards create that boundary, acting as a tangible obstacle and a visible deterrent while guiding and controlling entry points for monitoring and access control. They are designed to be part of a layered security approach, often paired with surveillance and alarms to detect breaches at the perimeter. Biometric access at interior doors operates after someone has already penetrated the outer boundary, making it an interior control rather than a perimeter one. Email security and firewall rules are cyber protections and do not constitute physical barriers.