CompTIA Cloud+ (CV0-004)SecurityMedium
A company is migrating sensitive financial data to a cloud object storage service. The compliance team mandates that the integrity of the data must be verifiable at any point in time, even if the data itself is encrypted. Which cryptographic technique is primarily used to ensure data integrity?
- AHashing
- BSymmetric Encryption
- CAsymmetric Encryption
- DDigital Signatures
Show answer & explanationAnswer & explanation
Correct answer: A. Hashing
Hashing is a cryptographic technique that generates a fixed-size unique digest (hash value) of data. Any alteration to the original data will result in a different hash value, thereby allowing verification of data integrity. While digital signatures also provide integrity, hashing is the fundamental mechanism for integrity checking.
Why the other options are wrong
- B. Symmetric encryption ensures confidentiality (data secrecy) but not integrity on its own.
- C. Asymmetric encryption provides confidentiality, authentication, and non-repudiation, but not direct data integrity checking like hashing.
- D. Digital signatures provide authenticity, non-repudiation, and integrity, but they rely on hashing as a core component for the integrity check. Hashing is the direct answer for ensuring data integrity.
Hashing for Integrity
Hashing is a cryptographic process that transforms data into a fixed-size string of characters (a hash value or digest), which is unique for each unique input, used to verify data integrity.
- Any change to input data results in a different hash output.
- One-way function; computationally infeasible to reverse.
- Commonly used to detect accidental or malicious data alteration.
Memory trick: Hashing verifies data's intact state.