Implementation of theExtended Schematic Protection
نویسندگان
چکیده
Protection models provide a formalism for specifying control over access to information and other resources in a multiuser computer system. One such model, the Extended Schematic Protection Model (ESPM), has expressive power equivalent to the mono-tonic access matrix model of Harrison, Ruzzo, and Ullman 7]. Yet ESPM retains tractable safety analysis for many cases of practical interest. Thus ESPM is a very general model, and it is of interest whether ESPM can be implemented in a reasonable manner. In this paper, we outline a distributed implementation for ESPM. Our implementation is capability-based, with an architecture where servers act as mediators to all subject and object access. Capabilities are made non-transferable by burying the identity of subjects in them, and unforgeable by using a public key encryption algorithm. Timestamps and public keys are used as mechanisms for revocation.
منابع مشابه
Implementation of the Extended Schematic Protection Model Paul
Protection models provide a formalism for specifying control over access to information and other resources in a multi-user computer system. One such model, the Extended Schematic Protection Model (ESPM), has expressive power equivalent to the monotonic access matrix model of Harrison, Ruzzo, and Ullman [7]. Yet ESPM retains tractable safety analysis for many cases of practical interest. Thus E...
متن کاملImplementation of the Extended Schematic Protection Model
Protection models provide a formalism for specifying control over access to information and other resources in a multi-user computer system. One such model, the Extended Schematic Protection Model (ESPM), has expressive power equivalent to the monotonic access matrix model of Harrison, Ruzzo, and Ullman [7]. Yet ESPM retains tractable safety analysis for many cases of practical interest. Thus E...
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We show the demand operation in the schematic protection model is redundant in that it can be simulated by copy and create operations. We also consider to what extent ampli cation (or conditional demand) can be simulated by similar constructions.
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