A Flexible Authorization Mechanism for Relational Data Management Systems

摘要

In this article, we present an authorization model that can be used to express a number of discretionary access control policies for relational data management systems. The model permits both positive and negative authorizations and supports exceptions at the same time. The model is flexible in that the users can specify, for each authorization they grant, whether The authorization can allow for exceptions or whether it must be strongly obeyed.