A security engineer is tasked with designing a system that ensures the integrity of data throughout its lifecycle, from creation to archival. The system must prevent unauthorized modification of data and maintain an audit trail of all changes. Furthermore, it must ensure that data is always transformed in a 'valid' state, adhering to strict business rules. Which security model is most effective for achieving these specific integrity goals?
- ABiba Security Model
- BNon-Interference Model
- CClark-Wilson Security Model
- DBell-LaPadula Security Model
Show answer & explanationAnswer & explanation
Correct answer: C. Clark-Wilson Security Model
The Clark-Wilson Security Model is uniquely focused on data integrity within commercial environments. It uses well-formed transactions and separation of duties to ensure that data is always transformed from one valid state to another. It introduces concepts like Constrained Data Items (CDIs), Unconstrained Data Items (UDIs), Integrity Verification Procedures (IVPs), and Transformation Procedures (TPs) to maintain data integrity and an audit trail, directly addressing the requirements.
Why the other options are wrong
- A. Biba focuses on integrity, preventing data corruption, but primarily through a 'no read-down, no write-up' approach, which is less about well-formed transactions and strict business rule adherence than Clark-Wilson.
- B. The Non-Interference Model focuses on information flow control, ensuring that actions of one group of users do not affect the output observed by another.
- D. Bell-LaPadula focuses on confidentiality, not integrity.
Clark-Wilson Security Model
An integrity model designed for commercial environments, focusing on well-formed transactions and separation of duties to maintain data integrity.
- Ensures data transitions from one valid state to another.
- Uses Integrity Verification Procedures (IVPs) and Transformation Procedures (TPs).
- Emphasizes separation of duties and auditing for integrity.
Memory trick: Clark-Wilson: Commercial Integrity, Clear Transactions.