Biba model

A formal, mathematical, state-transition model of integrity policy for multilevel-secure computer systems [Biba]. (See: source integrity. Compare: Bell-LaPadula model.)

Tutorial: This model for integrity control is analogous to the Bell-LaPadula model for confidentiality control. Each subject and object is assigned an integrity level and, to determine whether or not a subject is authorized for a particular access mode on an object, the integrity level of the subject is compared to that of the object. The model prohibits the changing of information in an object by a subject with a lesser or incomparable level. The rules of the Biba model are duals of the corresponding rules in the Bell-LaPadula model.