Modeling of MULTI SAFE Protection Enforcement Processes with Extended Petri Nets

The various kinds of access decision dependency within a predicate-based model of database protection are classified according to cost of enforcement. Petri nets and some useful extensions are described. Extended Petri nets are used to model the flow of messages and data during protection enforcement within MULTISAFE, a multimodule system architecture for secure database management. The model demonstrates that stated criteria for security are met within MULTISAFE. Of particular interest is the modeling of data dependent access conditions with predicates at Petri net transitions

MULTI SAFE -- A MODULAR MULTIPROCESSING APPROACH TO SECURE DATABASE MANAGEMENT

This paper describes the configuration and inter-module communication of a MULTIprocessor system for supporting Secure Authorization with Full Enforcement (MULTISAFE) for database management. A modular architecture is described which provides secure, controlled access to shared data in a multiuser environment--with low performance penalties, even for complex protection policies. The primary mechanisms are structured and verifiable. The entire approach is immediately extendible to distributed protection of distributed data. The system includes a user and applications module (UAM), a data storage and retrieval module (SRM), and a protection and security module (PSM). The control of intermodule communication is based on a data abstraction approach. It is initially described in terms of function invocations. An implementation within a formal message system is then described. The discussion of function invocations begins with the single terminal case and extends to the multiterminal case. Some physical implementation aspects are also discussed, and some examples of message sequences are given

Data bases and data base systems related to NASA's aerospace program. A bibliography with indexes

This bibliography lists 1778 reports, articles, and other documents introduced into the NASA scientific and technical information system, 1975 through 1980