Which statement best describes the domains covered by defense of the information infrastructure?

• A. It protects information assets in the cyber domain only.
• B. It protects information assets across physical, cyber, and information environments.
• C. It focuses only on encryption.
• D. It relates to personnel training.

Answer: (B)

Defense of the information infrastructure is a holistic effort that spans physical, cyber, and information environments. It isn’t enough to only protect networks and computers; you must also safeguard the physical assets and facilities (like servers, data centers, access controls, power, and environmental protections) and the information itself—the data, its flows, and how it’s used. When all three domains are protected, information assets remain secure even if one domain faces a threat.

Encryption is a valuable tool, but it addresses a specific protection goal within the information environment rather than defining the entire scope. Likewise, training personnel is essential, yet it alone doesn’t secure the networks or the physical components. The best description of defense of the information infrastructure is the broad protection of information assets across physical, cyber, and information environments.