CompTIA CASP+ (CAS-003) — Question 237

A security architect is designing a system to satisfy user demand for reduced transaction time, increased security and message integrity, and improved cryptographic security. The resultant system will be used in an environment with a broad user base where many asynchronous transactions occur every minute and must be publicly verifiable.
Which of the following solutions BEST meets all of the architect's objectives?

Answer options

• A. An internal key infrastructure that allows users to digitally sign transaction logs
• B. An agreement with an entropy-as-a-service provider to increase the amount of randomness in generated keys.
• C. A publicly verified hashing algorithm that allows revalidation of message integrity at a future date.
• D. An open distributed transaction ledger that requires proof of work to append entries.

Correct answer: D

Explanation

Option D is the best choice as an open distributed transaction ledger with proof of work provides the necessary public verification, security, and integrity required for such a system. Option A focuses on internal signing, which does not meet public verification needs. Option B addresses randomness but does not enhance transaction speed or integrity. Option C, while it allows future integrity checks, lacks real-time transaction verification and security enhancements.