An object-oriented security model for office environments

The authors present a security system for the protection of documents in an office information system. The system takes into consideration aspects of both dynamic changing of user activities and document sharing. The model the system is built on is based on the definition of role as a set of actions and responsibilities associated with a particular working activity. Access authorizations are specified according to roles. The role played by a user at a specific time identifies the working environment of the user and hence the operations that he/she can execute on documents. In modeling roles and documents the graph formalism and the inheritance mechanism are used. The use of an object-oriented programming language in the system realization allows an easy representation of the characteristics of the model