Solutions to the Polyinstantiation Problem

摘要

Polyinstantiation has generated a great deal of contrversy lately. Some haveargued that polyinstantiation and integrity are fundamentally incompatible, and have proposed alternatives to polyinstantiation. Others have argued about the correct definition of polyinstantiation and its operational semantics. The purpose of the report is to provide a tutorial on the subject. The report begins by reviewing the concept of polyinstantiation followed by a survey of various ways that have been proposed to deal with it. Finally, the impacts of various MLS DBMS architectures are discussed relative to polyinstantiation strategies. The report specifically discusses the differences between trusted subject and trusted computing base (TCB) subset with respect to polyinstantiation.