Protection and the control of information sharing in multics
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- Uthor M anuscripts E urope PM C Funders A uthor M anuscripts small subunit ribosomal DNA (nSSU-rDNA) locus (e.g., Agatha and Strüder-Kypke 2007; Dunthorn et al.
- The distance between the two C. henneguyi sequences is 2.69%; this same isolate had two different nSSU-rDNA sequences with a distance 0.12% (Dunthorn et al. 2008).
- The nSSU-rDNA data from Dunthorn et al. (2008) and the mtSSUrDNA here suggest that these two C. mucicola isolates may represent cryptic species.
- To account for the possibility of model and rate variation, the mtSSU-rDNA alignment was also analyzed using a second method of Bayesian inference that used a Dirichlet processes of different GTR matrices for a model of evolution as implemented in PhyloBayes (Lartillot and Philippe 2004; Lartillot et al. 2009); hereafter referred to as the PhyloBayes tree.
- Within the shallow relationships in the Colpodida, node support is variable and there is a lack of resolution for many relationships from both molecular markers (Figs 1–3, 6–11).
- For all constrains, internal relationships within the constrained groups was unspecified, and relationships among the remaining taxa were unspecified as well.
- Agatha S, Strüder-Kypke M. Phylogeny of the order Choreotrichida (Ciliophora, Spriotricha, Oligotrichea) as inferred from morphology, ultrastructure, ontogenesis, and SSr-RNA sequences.
- Catania F, Wurmser F, Potekhin AA, Przyboś E, Lynch M. Genetic diversity in the Paramecium aurelia species complex.
- Hillis DM, Pollock DD, McGuire JA, Zwickl DJ.
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Cites background from "Protection and the control of infor..."
...…authentication; statistics; information theory; data mining; I. INTRODUCTION Text passwords have dominated human-computer authentication since the 1960s  and been derided by security researchers ever since, with Multics evaluators singling passwords out as a weak point in the 1970s ....
Cites background or methods from "Protection and the control of infor..."
...6.1 Hardware Support for Modularity The major hardware approaches to improve reliability include capability-based architectures [Houdek et al. 1981; Organick 1983; Levy 1984] and ring and segment architectures [Intel Corporation 2002; Saltzer 1974]....
...The major hardware approaches to improve reliability include capability-based architectures [25, 30, 36] and ring and segment architectures [27, 40]....
"Protection and the control of infor..." refers methods in this paper
...PDP-| time-sharing system  and the CAL time-sharing system , although almost every recent protection system design includes provision for this feature and many have proposed schemes more elegant and powerful than the Multics protection rings [22, 25, 35]....
"Protection and the control of infor..." refers background in this paper
..., the Multics virtual memory is segmented to permit sharing of objects in the virtual memory and to simplify address space management for the programmer....
...By virtue of a complete set of backpointers (see  for details) any change to an access control list is immediately propagated to all descriptors which have been derived from it....
...The reasons why the first step provides simplification for the user have been discussed extensively in the literature [4, 15]....
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This paper describes the design of mechanisms to control sharing of Information in the Multics system. The paper ends with a discussion of several known weaknesses in the current protection mechanism design. The Multics system *, a prototype computer utility, serves as a useful case study of the protection mechanisms needed to permit controlled sharing of information in an on-line, general-purpose, information-storing system. This paper provides a survey of the various techniques currently used in Multics to provide controlled sharing, user authentication, inter-user isolation, supervisor-user protection, user-written proprietary programs, and control of special privileges. Rather than trying to document every detail of a changing environment, this paper concentrates on the protection strategy of Multics, with the goal of communicating those ideas which can be applied or adapted to other operating systems. This research was supported by the Advanced Research Projects Agency of the Department of Defense under ARPA Order No. 2095 which was monitored by ONR Contract No. NOQ014-70-A-0362-0006. * A brief description of Multics, and a more complete bibliography, are given in the paper by Corbató, Saltzer, and Clingen [ 6 ].