Manfred Ruschitzka

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This paper describes a specification-based approach to detect exploitations of vulnerabdities in security-critical programs. The approach utilizes security specifications that describe the intended behavior of programs and scans audit trails for operations that are in violation of the specifications. We developed a formal framework for specifying the(More)
Committee in Charge 1996 i Acknowledgements I a m d eeply indebted to m y advisors, Karl Levitt a n d Manfred Ruschitzka. Without their help and guidance, I was not able to nish this work. Special thanks to Karl for his precious time a n d e n ergy, a n d h i s p a tience in teaching m e not only how t o perform research, but also how to write proposals,(More)
This paper presents a scheme for classifying scheduling algorithms based on an abstract model of a scheduling system which formalizes the notion of priority. Various classes of scheduling algorithms are defined and related to existing algorithms. A criterion for the implementation efficiency of an algorithm is developed and results in the definition of(More)
A widely used error recovery technique in database systems is the rollback and recovery technique. This technique saves periodically the state of the system and records all activities on a reliable log tape. The operation of saving the system state is called <italic>checkpointing.</italic> The elapsed time between two consecutive checkpointing operations is(More)
While the adoption of an implementation project for an operating systems course is certainly beneficial, non-trivial projects are inherently demanding in terms of student efforts and computer costs. This paper reports on a project which has been designed to keep the effort for an extensive simulation of a contemporary system within acceptable limits. The(More)
The interactive exchange and translation of data between heterogeneuus computer systems depend not only on hardware and o p ersting-system characteristics, But also on the proprietary format imposed by the software systems maintaining it. For functionally comparable software systems, we present a syntax-driven translation methodology based on environment(More)