In cyber-physical security, defense-in-depth is best described as

In cyber-physical security, defense-in-depth is best described as

• A. Multiple layers of protection across digital and physical assets
• B. Relying solely on cameras for security
• C. Isolating IT and facilities security entirely
• D. Single robust barrier protecting all assets

Answer: (A)

Defense-in-depth in cyber-physical security means building multiple, overlapping layers of protection that span both digital systems and physical assets. It combines physical safeguards (fences, access controls, alarms, guards), cyber defenses (authentication, encryption, segmentation, monitoring, patching), and recovery measures (backups, incident response, redundancy). The idea is that if one layer is breached or fails, others still stand to deter, detect, or slow down the attacker and reduce the impact. For example, even if a breach starts with compromised credentials, physical access controls and real-time surveillance can reveal the intrusion, while network monitoring and segmentations can limit lateral movement and protect critical systems. This approach—multiple layers of protection across digital and physical assets—best captures the concept. It avoids overreliance on a single measure like cameras, and it emphasizes integration rather than isolating IT from facilities or relying on a single barrier, which would create a single point of failure.

Defense-in-depth in cyber-physical security means building multiple, overlapping layers of protection that span both digital systems and physical assets. It combines physical safeguards (fences, access controls, alarms, guards), cyber defenses (authentication, encryption, segmentation, monitoring, patching), and recovery measures (backups, incident response, redundancy). The idea is that if one layer is breached or fails, others still stand to deter, detect, or slow down the attacker and reduce the impact. For example, even if a breach starts with compromised credentials, physical access controls and real-time surveillance can reveal the intrusion, while network monitoring and segmentations can limit lateral movement and protect critical systems. This approach—multiple layers of protection across digital and physical assets—best captures the concept. It avoids overreliance on a single measure like cameras, and it emphasizes integration rather than isolating IT from facilities or relying on a single barrier, which would create a single point of failure.