Which control protects data both at rest and in transit by using cryptographic techniques?

Which control protects data both at rest and in transit by using cryptographic techniques?

• A. Identity Federation
• B. Network Segmentation
• C. Data Encryption
• D. Access Enforcement

Answer: (C)

Data Encryption uses cryptographic techniques to protect the contents of data both when it is stored and when it is moving across networks. When data is at rest, encryption renders stored information unreadable without the proper decryption key, so a stolen disk or compromised database doesn’t reveal the actual data. When data is in transit, encryption protects it from eavesdropping and tampering as it travels between systems, using protocols like TLS or IPsec. This combination directly protects confidentiality in both states, which is why encryption is the best fit. By comparison, identity federation focuses on authenticating identities, network segmentation limits where data can travel, and access enforcement governs who can access resources—none of these inherently encrypt data themselves.

Data Encryption uses cryptographic techniques to protect the contents of data both when it is stored and when it is moving across networks. When data is at rest, encryption renders stored information unreadable without the proper decryption key, so a stolen disk or compromised database doesn’t reveal the actual data. When data is in transit, encryption protects it from eavesdropping and tampering as it travels between systems, using protocols like TLS or IPsec. This combination directly protects confidentiality in both states, which is why encryption is the best fit. By comparison, identity federation focuses on authenticating identities, network segmentation limits where data can travel, and access enforcement governs who can access resources—none of these inherently encrypt data themselves.