Biba Integrity Model add on to BLP

Lattice-Based uses less than or equal to relation

A lattice structure is a set with a least upper bound (LUB) and a greatest lower bound (GLB)

Lattice represents a set of integrity classes (IC) and an ordered relationship

Lattice = (IC, LUB, GUB)

Integrity – who created this order – who classified this order?

Integrity Axioms

The Simple Integrity Axiom - no reading of lower object from higher subject (No Read Down)

The * (star) Integrity Axiom – No writing from lower subject to higher object (No write Up)

A subject at a lower level of integrity can not invoke a subject at a higher level of integrity

Clark-Wilson Integrity Model (Integrity for Commercial Environments)

Two elements: well-formed transaction and separation of duties.

Developed in 1987 for use in real-world commercial environment

Addresses the three integrity goals

Constrained Data Item (CDI) – A data Item whose integrity is to be preserved

Integrity Verification Procedure (IVP) – confirms that all CDIs have integrity

Transformation Procedure (TP) – transforms a CDI from one integrity state to another integrity state

Unconstrained Data Item – data items outside of the control area of the modeled environment

Requires Integrity Labels

Clark-Wilson Integrity Model

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