Data items in a database are semantically related. Thus, the access control mechanism of a database system must be concerned with the possibility that access to one item may violate a denied access to another item. This study concentrates on two basic semantic relations for protection requirements. By utilizing a graph-theoretic approach, some of the fundamental properties of the protection relations can be readily identified. These properties can then be used as a basis for understanding more general context dependent protection requirements. Two fundamental properties of the two protection relations are found. The first property addresses the question: given a database with a set of protection relations, is it possible to find a maximal subset of the database such that access to one item of the subset will not lead to any violation of a denied access to another item? The second property addresses the question: given a database with a set of protection relations, is it possible to find a sequence of accesses such that the protection requirement is enforced with no violation?

This tutorial is extracted from the recently completed monograph, Computer Security: Its Problems and Solutions [3], and is intended as a technical review of research in the areas of operating system security. Furthermore, it is intended to provide some assessment and evaluation of the work reviewed. Some projections and speculations of future activities in operating system research are also included. Because the tutorial is written for technical people who are not directly conducting such research, we have tried to present the review in an illustrative manner with intuitive and informal definitions of the necessary technology. The tutorial expounds the notion of surveillance in terms of logging and threat monitoring. It conceptualizes the problems and solutions of access control. To achieve security, the operating system relies on isolation. The tutorial points out the trade-off between security and cost of isolation. Furthermore, it illustrates two impor tant isolation methods. In order to provide security, the operating system must be designed and implemented as a secure system. The use of verification techniques for proving the correctness of secure operating system design and implementation is examined. When the operating system is large and the security requirements are elaborate, it may be necessary to concentrate the secure elements in a kernel. The notion of secure kernel is therefore examined. Other methods such as penetration tests are also examined An up-to-date bibliography since 1974 is included. To allow the readers to have a coherent coverage of various topics of operating system security, we have endeavored to give our personal views of various subject matters. We would like the reader to bear with us in the expression of these views.

Ohio State's school year is divided into four quarters, each ten weeks long. It is possible to schedule classes to meet three, four, or five hours per week. (The latter with 50 class meetings is similar to a three semester hour course.) Most students attend classes for three of the four quarters. Because the amount of material covered in a programming class is proportional to the number and quality of programs completed, we have chosen a two quarter sequence, each course meeting three days a week. The students receive four quarter hours credit (one hour of laboratory credit) for each course. The students in this sequence are mostly computer and information science majors, but there are also many mathematics and some science and engineering majors. There are other courses for administrative science, engineering and other non-technical students. All the introductory courses are taught by graduate students under the supervision of a faculty member.

Data base systems are intended to help in the storage and retrieval of information which is needed to make decisions in an organization. Senko [7] has stated that we should try to assure "(1) the efficient use of human resources in the design, implementation, and utilization of information systems, and (2) the efficient utilization of the physical mechanical resources of the systems themselves."

Computer and Information Science Departments are usually organized, as was the one at The Ohio State University, by combining already existing courses in computer programming and applications from other departments into one department and adding a few extra courses. This paper is a report concerning how this was done at Ohio State and how the Department has developed since. Suggestions are also included for the organization of new departments at other schools. The report has been arranged in four main sections: a description of the development of the department at Ohio State, a unifying philosophy of the field, a description of the Ohio State undergraduate curriculum in Computer and Information Science, and suggestions for new curricula at other schools.