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Explore the concepts of Typed Access Matrix Model (TAM) and Augmented TAM (ATAM) for stronger security results and expressive operations. Learn about single object TAM, canonical schemes, and safety ternary MTAM for advanced access control.
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The Typed Access Matrix Model (TAM) and Augmented TAM (ATAM) Ravi Sandhu Laboratory for Information Security Technology George Mason University www.list.gmu.edu sandhu@gmu.edu
TAM: Typed Access Matrix Model TAM adds types to HRU and preserves strong safety results of SPM/ESPM SO-TAM: Single Object TAM SO-TAM manipulates one column of the access matrix at a time and is equivalent to TAM ATAM: Augmented TAM ATAM adds testing for absence of rights to TAM ATAM is equivalent to TAM in one sense but more expressive in another Outline
Binary and Unary MTAM • Unary MTAM • Useless • Binary MTAM • Single-parent creation or spontaneous double-child creation • Less expressive than multi-parent creation
SOTAM • SOTAM is equivalent in expressive power to TAM
ATAM: Augmented TAM • Allow testing for absence of rights in the conditions of commands • ATAM is equivalent in expressive power to TAM in unbounded simulation but most likely not in bounded simulation • “Most likely not” has recently been shown to be “provably cannot”