Considerations on TCB subsetting

The hierarchical trusted computing base (TCB) subsetting architecture, which is intended to allow database management systems (DBMSs) to take advantage of the effort expended in producing and evaluating trusted multilevel operating systems, is discussed. The advantages and disadvantages that result from the use of this security architecture are explored. Another architecture, functional modularization of a TCB, is presented. This architecture gives the DBMS much greater control over its security policy and resource management than the TCB subsetting approach, allowing the fuller functionality and performance