Protection of Shared Objects for Cooperative Work

This paper discusses the design of a system for the protection of shared persistent information objects that are intended to provide a basis for building cooperative applications. A task-based model of cooperative work is adopted and user and task requirements are based on an earlier case study undertaken by the authors. The key problem addressed is the mapping of user-level protection specifications onto groups of programming-level objects. A design for a two-level protection model to address this problem is outlined. January 31, 1995 1 1. Introduction This paper discusses the requirements for the protection of information in cooperative work and describes an approach to the design of a protection system. The design is intended for use in an otherwise open software environment in which cooperative tasks are carried out using cooperative applications accessing shared long-lived information objects in a distributed environment. Application software is assumed to be object-oriented, ..