EARLY PERFORMANCE PREDICTION METHODOLOGY FOR MANY-CORES ON CHIP BASED APPLICATIONS

Modern high performance computing applications such as personal computing, gaming, numerical simulations require application-specific integrated circuits (ASICs) that comprises of many cores. Performance for these applications depends mainly on latency of interconnects which transfer data between cores that implement applications by distributing tasks. Time-to-market is a critical consideration while designing ASICs for these applications. Therefore, to reduce design cycle time, predicting system performance accurately at an early stage of design is essential. With process technology in nanometer era, physical phenomena such as crosstalk, reflection on the propagating signal have a direct impact on performance. Incorporating these effects provides a better performance estimate at an early stage. This work presents a methodology for better performance prediction at an early stage of design, achieved by mapping system specification to a circuit-level netlist description. At system-level, to simplify description and for efficient simulation, SystemVerilog descriptions are employed. For modeling system performance at this abstraction, queueing theory based bounded queue models are applied. At the circuit level, behavioral Input/Output Buffer Information Specification (IBIS) models can be used for analyzing effects of these physical phenomena on on-chip signal integrity and hence performance. For behavioral circuit-level performance simulation with IBIS models, a netlist must be described consisting of interacting cores and a communication link. Two new netlists, IBIS-ISS and IBIS-AMI-ISS are introduced for this purpose. The cores are represented by a macromodel automatically generated by a developed tool from IBIS models. The generated IBIS models are employed in the new netlists. Early performance prediction methodology maps a system specification to an instance of these netlists to provide a better performance estimate at an early stage of design. The methodology is scalable in nanometer process technology and can be reused in different designs

Revisión sistemática de sistemas inteligentes de transporte (ITS) a través de internet de las cosas (IOT) para problemas de transporte terrestre de pasajeros

Trabajo de InvestigaciónEl desarrollo de este trabajo fue realizar una revisión sistemática de sistemas inteligentes de transporte (ITS) a través de internet de las cosas (IOT) para problemas de transporte terrestre de pasajeros, siguiendo la metodología de revisión sistemática de Barbara Kitchenham, definiendo palabras y frases para generar cadenas de busqueda e ir agregando criterios de inclusión y exclusión, en el proceso de búsqueda en bases de datos científicas, con el fin de realizar un análisis cuantitativo, mostrando una caracterización de términos referentes a la investigación.INTRODUCCIÓN 1. GENERALIDADES 2. PLANIFICACION DE LA REVICION SISTEMATICA. 3. RESULTADOS CONCLUCIONES RECOMENDACIONES BIBLIOGRAFÍA ANEXOSPregradoIngeniero de Sistema

Mechanisms for service-oriented resource allocation in IoT

Albeit several IoT applications have been recently deployed in several fields, including environment and industry monitoring, Smart Home, Smart Hospital and Smart Agriculture, current deployments are mostly host-oriented, which is undoubtedly limiting the attained benefits brought up by IoT. Indeed, future IoT applications shall benefit from service-oriented communications, where the communication establishment between end-points is not dependent on prior knowledge of the host devices in charge of providing the service execution. Rather, an end-user service execution request is mapped into the most suitable resources able to provide the requested service. Furthermore, this model is a key enabler for the design of future services in Smart Cities, e-Health, Intelligent Transportation Systems, among other smart scenarios. Recognized the benefits of this model in future applications, considerable research effort must be devoted for addressing several challenges yet unsolved, such as the ones brought up by the high dynamicity and heterogeneity inherent to these scenarios. In fact, service-oriented communication requires an updated view of available resources, mapping service requests into the most suitable resources taking several constraints and requirements into account, resilience provisioning, QoS-aware service allocation, just to name a few. This thesis aims at proposing and evaluating mechanisms for efficient resource allocation in service-oriented IoT scenarios through the employment of two distinct baseline technologies. In the first approach, the so-called Path Computation Element (PCE), designed to decouple the host-oriented routing function from GMPLS switches in a centralized element, is extended to the service-oriented PCE (S-PCE) architecture, where a service identifier (SID) is used to identify the service required by an end-user. In this approach, the service request is mapped to one or a set of resources by a 2-steps mapping scheme that enables both selection of suitable resources according to request and resources characteristics, and avoidance of service disruption due to possible changes on resources¿ location. In the meantime, the inception of fog computing, as an extension of the cloud computing concept, leveraging idle computing resources at the edge of the network through their organization as highly virtualized micro data centers (MDC) enabled the reduction on the network latency observed by services launched at edge devices, further reducing the traffic at the core network and the energy consumption by network and cloud data center equipment, besides other benefits. Envisioning the benefits of the distributed and coordinated employment of both fog and cloud resources, the Fog-to-Cloud (F2C) architecture has been recently proposed, further empowering the distributed allocation of services into the most suitable resources, be it in cloud, fog or both. Since future IoT applications shall present strict demands that may be satisfied through a combined fog-cloud solution, aligned to the F2C architecture, the second approach for the service-oriented resource allocation, considered in this thesis, aims at providing QoS-aware resource allocation through the deployment of a hierarchical F2C topology, where resource are logically distributed into layers providing distinct characteristics in terms of network latency, disruption probability, IT power, etc. Therefore, distinct strategies for service distribution in F2C architectures, taking into consideration features such as service transmission delay, energy consumption and network load. Concerning the need for failure recovery mechanisms, distinct demands of heterogeneous services are considered in order to assess distinct strategies for allocation of protection resources in the F2C hierarchy. In addition, the impact of the layered control topology on the efficient allocation of resources in F2C is further evaluated. Finally, avenues for future work are presented.Aunque son ya varias las aplicaciones que se han desarrollado en el área de IoT, especialmente en el campo ambiental, Smart Home o Smart Health, las implementaciones actuales son en su mayoría ¿host-oriented¿, lo que sin duda limita sus potenciales beneficios. Una posible estrategia para reducir esos efectos negativos se centra en que las futuras aplicaciones se beneficien de las comunicaciones orientadas a servicios, ¿service-oriented¿, donde el establecimiento de comunicación entre puntos finales no depende del conocimiento previo de los hosts a cargo de proporcionar la ejecución del servicio. En este escenario, una solicitud de ejecución de servicio se asigna a los recursos más adecuados capaces de proporcionar el servicio solicitado. Este modelo se considera clave para el despliegue de futuros servicios en Smart Cities, e-Health, Intelligent Transportation Systems, etc. Reconocidos los beneficios de este modelo en las aplicaciones futuras, un substancial esfuerzo de investigación es necesario para abordar varios desafíos aún no resueltos, como los surgidos por la alta dinámica y heterogeneidad inherente a estos escenarios. De hecho, la comunicación service-oriented requiere una vista actualizada de los recursos disponibles, así como la asignación de solicitudes de servicio en los recursos más adecuados teniendo en cuenta varias restricciones y requisitos. Esta tesis tiene como objetivo proponer y evaluar mecanismos para la asignación eficiente de recursos en escenarios IoT orientados a servicios a través del empleo de dos tecnologías básicas distintas. En el primer enfoque, el llamado Path Computation Element (PCE), diseñado para desacoplar la función de enrutamiento de los conmutadores GMPLS hacia un elemento centralizado, se extiende generando la arquitectura service-oriented PCE (S-PCE). En S-PCE se utiliza un identificador de servicio (SID) para identificar el servicio requerido por un usuario final, y la solicitud se asigna, bien a uno o bien a un conjunto de recursos, mediante un esquema de asignación de 2 pasos que permite la selección de los recursos adecuados, evitando la interrupción del servicio debido a posibles cambios en la ubicación de los recursos. Mientras tanto, el inicio de Fog computing, como una extensión de Cloud computing, basado conceptualmente en aprovechar la infraestructura y los recursos inactivos en el extremo de la red a través de su organización como micro data centers (MDC), ha supuesto la reducción de la latencia de la red para los servicios lanzados por dispositivos localizados en el extremo de la red, reduciendo el tráfico en el centro de la red (backbone) así como el consumo de energía, además de otros beneficios. Asumiendo las ventajas de la utilización distribuida y coordinada de los recursos fog y cloud, la arquitectura Fog-to-Cloud (F2C) ha sido recientemente propuesta, destinada a potenciar la asignación distribuida de servicios en los recursos más adecuados, sea en cloud, fog o ambos. Dado que las futuras aplicaciones IoT deben presentar demandas que podrían ser satisfechas a través de una solución alineada con la arquitectura F2C, el segundo enfoque para la asignación de recurso orientado a servicio, considerado en esta tesis, tiene como objetivo proporcionar una asignación de recursos mediante el despliegue de una topología F2C, donde los recursos se distribuyen lógicamente en capas que proporcionan características distintas en términos de latencia de red, probabilidad de interrupción, etc. Así, se proponen distintas estrategias para la distribución de servicios, teniendo en cuenta características tales como QoS y consumo de energía. Con respecto a la necesidad de mecanismos de recuperación de fallos, se evalúan distintas estrategias para la asignación de recursos de protección en la jerarquía F2C. Además, se evalúa el impacto de la topología de control en capas sobre la asignación eficiente de recursos en F2C. Finalmente, las sugerencias para trabajos futuros son presentadas

Clemson Catalog, 2010-2011, Volume 85

https://tigerprints.clemson.edu/clemson_catalog/1160/thumbnail.jp

Aeronautical engineering: A continuing bibliography with indexes (supplement 323)

This bibliography lists 518 reports, articles, and other documents introduced into the NASA scientific and technical information system in November 1995. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment, and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

Aeronautical engineering: A continuing bibliography with indexes (supplement 277)

This bibliography lists 467 reports, articles, and other documents introduced into the NASA scientific and technical information system in Mar. 1992. Subject coverage includes: the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines); and associated aircraft components, equipment, and systems. It also includes research and development in ground support systems, theoretical and applied aspects of aerodynamics, and general fluid dynamics

Architecture de sécurité de bout en bout et mécanismes d'autoprotection pour les environnements Cloud

Since several years the virtualization of infrastructures became one of the major research challenges, consuming less energy while delivering new services. However, many attacks hinder the global adoption of Cloud computing. Self-protection has recently raised growing interest as possible element of answer to the cloud computing infrastructure protection challenge. Yet, previous solutions fall at the last hurdle as they overlook key features of the cloud, by lack of flexible security policies, cross-layered defense, multiple control granularities, and open security architectures. This thesis presents VESPA, a self-protection architecture for cloud infrastructures. Flexible coordination between self-protection loops allows enforcing a rich spectrum of security strategies. A multi-plane extensible architecture also enables simple integration of commodity security components.Recently, some of the most powerful attacks against cloud computing infrastructures target the Virtual Machine Monitor (VMM). In many case, the main attack vector is a poorly confined device driver. Current architectures offer no protection against such attacks. This thesis proposes an altogether different approach by presenting KungFuVisor, derived from VESPA, a framework to build self-defending hypervisors. The result is a very flexible self-protection architecture, enabling to enforce dynamically a rich spectrum of remediation actions over different parts of the VMM, also facilitating defense strategy administration. We showed the application to three different protection scheme: virus infection, mobile clouds and hypervisor drivers. Indeed VESPA can enhance cloud infrastructure securityLa virtualisation des infrastructures est devenue un des enjeux majeurs dans la recherche, qui fournissent des consommations d'énergie moindres et des nouvelles opportunités. Face à de multiples menaces et des mécanismes de défense hétérogènes, l'approche autonomique propose une gestion simplifiée, robuste et plus efficace de la sécurité du cloud. Aujourd'hui, les solutions existantes s'adaptent difficilement. Il manque des politiques de sécurité flexibles, une défense multi-niveaux, des contrôles à granularité variable, ou encore une architecture de sécurité ouverte. Ce mémoire présente VESPA, une architecture d'autoprotection pour les infrastructures cloud. VESPA est construit autour de politiques qui peuvent réguler la sécurité à plusieurs niveaux. La coordination flexible entre les boucles d'autoprotection réalise un large spectre de stratégies de sécurité comme des détections et des réactions sur plusieurs niveaux. Une architecture extensible multi plans permet d'intégrer simplement des éléments déjà présents. Depuis peu, les attaques les plus critiques contre les infrastructures cloud visent la brique la plus sensible: l'hyperviseur. Le vecteur d'attaque principal est un pilote de périphérique mal confiné. Les mécanismes de défense mis en jeu sont statiques et difficile à gérer. Nous proposons une approche différente avec KungFuVisor, un canevas logiciel pour créer des hyperviseurs autoprotégés spécialisant l'architecture VESPA. Nous avons montré son application à trois types de protection différents : les attaques virales, la gestion hétérogène multi-domaines et l'hyperviseur. Ainsi la sécurité des infrastructures cloud peut être améliorée grâce à VESP

Aeronautical engineering, a continuing bibliography with indexes

This bibliography lists 823 reports, articles, and other documents introduced into the NASA scientific and technical information system in November 1984

LIPIcs, Volume 274, ESA 2023, Complete Volume

LIPIcs, Volume 274, ESA 2023, Complete Volum