What are common encryption concepts relevant to MDC3?

• A. Encryption concepts include data encryption at rest, encryption in transit, key management, rotation, and selecting appropriate algorithms to protect data in MDC3.
• B. Encryption is only about compressing data.
• C. Encryption is the same as hashing.
• D. Encryption is irrelevant to MDC3.

Answer: (A)

In MDC3, protecting data confidentiality comes from a set of practical encryption practices that cover how data is secured both when stored and when it moves, as well as how the cryptographic keys are handled. Data encryption at rest and encryption in transit are the foundation: encryption at rest protects files, databases, and backups on storage systems, so even if someone gains access to the storage, they can’t read the data; encryption in transit protects data as it travels across networks, preventing eavesdropping and tampering.

Key management is crucial because the strength of encryption depends on how well keys are created, stored, accessed, and controlled. Rotation—periodically updating keys—limits the window of opportunity if a key is compromised, and proper key lifecycle practices (generation, distribution, revocation, and retirement) are essential for maintaining security over time. Choosing appropriate algorithms and configurations matters too, ensuring you use strong, standards-based options (for example, AES for data at rest, TLS for data in transit, and secure, modern public-key algorithms) that align with performance needs and regulatory requirements.

So, the best answer highlights these interconnected concepts—how data is encrypted both on disk and in transit, how keys are managed and rotated, and how selecting the right algorithms fits into a comprehensive protection strategy for MDC3.

Compression, hashing, and treating encryption as irrelevant don’t fit because compression is a different technique for reducing size, hashing provides data integrity rather than confidentiality, and encryption is indeed relevant to MDC3.