: "No Read Down" – a subject cannot read data at a lower integrity level to avoid being "tainted" by low-quality info. -Integrity Axiom
These models are designed to prevent unauthorized disclosure of information, often used in government and military environments. Information Security Models Pdf
: Focused on integrity . It mirrors Bell-LaPadula with a "No Read Down, No Write Up" rule, preventing low-integrity data from corrupting high-integrity systems. : "No Read Down" – a subject cannot
1976. Core Focus: A theoretical model for access control matrices. Key Insight: It formalizes how access permissions (read, write, own) can be transferred between subjects and objects. It is famous for proving that "safety" (deciding if a subject can ever acquire a specific right) is undecidable in certain cases. Who Cares: Operating system designers and academic cryptographers. Most CISSP aspirants only need a high-level summary. It mirrors Bell-LaPadula with a "No Read Down,
Uses and well-formed transactions to maintain internal consistency. Brewer-Nash (Chinese Wall) Conflict of Interest