Towards a strategy for Achieving security and multi-user integrity in knowledge base systems

Security means that a user may only access a subset of the total information, namely that informationfor which access permission has been granted. lntegrity concerns the correctness of the information. The implementation of security means that integrity must not only be consideredfor all information in the system, but also for each subset which a user may access. We propose an information organizational structure and policy which permits security criteria to be specified for constraints and supports multi-user integrity, ie. integrity of the whole knowledge base as well as integrity of each user's subset of the knowledge base. Our approach specifies an area of the knowledge base for those objects which meet the integrity constraints for a particular user but not the integrity requirements of the knowledge base as a whole. In addition, to enable a user to achieve a consistent subset of the knowledge base information may be marked with a "pending" status. We are implementing this approach via the Group Security model in ConceptBase, a knowledge base management system developed at the University of Passau