We propose in this paper an algebraic approach to hard-ware/software partitioning in Verilog Hardware Description Language (HDL). We explore a collection of algebraic laws for Verilog programs, from which we design a set of syntax-based algebraic rules to conduct hardware/software partitioning. The co-specification language and the target hardware and software description languages are specific subsets of Verilog. Through this, we confirm successful verification for the correctness of the partitioning process by an algebra of Verilog. Facilitated by Verilog’s rich features, we have also successfully studied hw/sw partitioning for environment-driven systems. / Singapore-MIT Alliance (SMA)

Made available in DSpace on 2014-06-12T16:00:02Z (GMT). No. of bitstreams: 2 arquivo5819_1.pdf: 1022780 bytes, checksum: 817e10825cb544dad97eed36627fdd51 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Uma abordagem formal e crucial na especificação e desenvolvimento de sistemas complexos. Inspirado pela engenharia, o desenvolvimento de software deve preterir a abordagem empirica e seguir uma abordagem estruturada, formal, passível de repetição e prova face ao advento de sistemas mais complexos, paralelos e concorrentes. Este trabalho apresenta uma extensão conservativa de OhCircus, uma linguagem de especificação oncorrente, que integra CSP, Z, orientação a objetos e um calculo de re- finamento. Esta extensão suporta a definição de heranca de processo, onde uxo de controle, operações e componentes de estado em um superprocesso, podem ser reusados por seus subprocessos. Neste trabalho nos apresentamos a gramatica estendida de OhCir- cus, acompanhada por um conjunto de regras de tipos que lidam com as novas construções da linguagem. Nos apresentamos, em termos da Unifying Theories of Programming definida por Hoare e He, a semântica formal de heranca de processo e suas construções de suporte. A principal contribuição deste trabalho e um conjunto, formalmente provado, de leis algebricas que lidam com herança de processo. Nós também explanamos informalmente como essas leis podem contribuir para uma teoria de completude para OhCircus. Finalmente nossas leis são exercitadas atraves de um estudo de caso

Un service du nuage peut employer des techniques de sécurités pour assurer la sécurité de l’information. Ces techniques protègent une donnée personnelle en la rendant inintelligible pour toutes personnes autres que l’utilisateur du service. En contrepartie, certaines fonctionnalités ne peuvent plus être implémentées. Par exemple, la technique du chiffrement symétrique rend les données inintelligibles, mais empêche le calcul sur ces données.Cette thèse avance qu’un service du nuage doit composer les techniques pour assurer la sécurité de l’information sans perdre de fonctionnalités. Elle se base sur l’étude de la composition de trois techniques qui sont le chiffrement, la fragmentation verticale et les calculs côté client. Cette étude montre que la composition sécurise sans perdre de fonctionnalités, mais complexifie l’écriture du service. La thèse propose alors un nouveau langage pour l’écriture de services du nuage qui assurent la sécurité des données personnelles par compositions des techniques de sécurité.Ce langage est muni de lois algébriques pour dériver,systématiquement, un service local sans protection vers son équivalent sécurisé du nuage. Le langage est implémenté en Idris et profite de son système de type expressif pour vérifier la composition correcte des techniques de cryptographie. Dans le même temps, un encodage traduit le langage en ProVerif, un vérificateur de modèle pour l’analyse automatique des propriétés de sécurité sur les protocoles cryptographiques. Cette traduction vérifie alors la sécurité des données personnelles dans le service. / A cloud service can use security techniques to ensure information privacy. These techniques protect privacy by converting the client’s personal data into unintelligible text. But they can also cause the loss of some functionalities of the service. For instance, a symmetric-key cipher protects privacy by converting readable personal data into unreadable one. However, this causes the loss of computational functionalities on this data.This thesis claims that a cloud service has to compose security techniques to ensure information privacy without the loss of functionalities. This claim is based on the study of the composition of three techniques: symmetric cipher, vertical data fragmentation and client-side computation. This study shows that the composition makes the service privacy preserving, but makes its formulation overwhelming. In response, the thesis offers a new language for the writing of cloud services that enforces information privacy using the composition of security techniques. This language comes with a set of algebraic laws to systematically transform a local service without protection into its cloud equivalent protected by composition. An Idris implementation harnesses the Idris expressive type system to ensure the correct composition of security techniques. Furthermore, an encoding translates the language intoProVerif, a model checker for automated reasoning about the security properties found in cryptographic protocols. This translation checks that the service preserves the privacy of its client.