CompTIA SecurityX (CAS-005) — Question 305

Previously intercepted communications must remain secure even if a current encryption key is compromised in the future. Which of the following best supports this requirement?

Answer options

• A. Tokenization
• B. Key stretching
• C. Forward secrecy
• D. Simultaneous authentication of equals

Correct answer: C

Explanation

Forward secrecy guarantees that even if the current encryption key is compromised, previous communication sessions remain secure because they were encrypted with different, ephemeral keys. Tokenization, key stretching, and simultaneous authentication of equals do not provide this level of protection for past communications.