Forwarding Web Service Requests To A Single Service Instance in Service Oriented Networking

Abstract: Service providers within an enterprise network are often governed by client service contracts (CSC) that specify, among other constraints, the rate at which a particular service instance may be accessed. The service can be accessed via multiple points in a proxy tier configuration. The CSC and thus the rate specified have to be collectively respected by all the middleware appliances. The appliances locally shape the service requests to respect the global contract. Investigation is done in the case where the CSC limits the rate to a service to X requests with an enforcement/observation interval of T seconds. This paper extends, and investigates the Credit-based Algorithm in a production level enterprise network setting. CBA is a decentralized algorithm for service traffic shaping in middleware appliances

Study of encapsulation and transport of 3DTV by satellite

The project was developed in EADS ASTRIUM Toulouse in the framework of the MUSCADE project with the latest technologies in 3DTV. Currently most of the research in satellite broadcasting field is focused in 3DTV transmission as the following of HDTV. MUSCADE is a European project funded by the 7th Framework Program whose objective is to demonstrate a complete multiview 3DTV live chain over wireline, wireless and satellite networks. This project aims to set up a satellite testbed to validate the 3D content format defined by MUSCADE in an emulated satellite environment. The document’s first chapter describes the environment where the internship has taken place and a brief overview of the EADS Company. After, a short description of the whole MUSCADE project can be found in section 5. This allows the reader to achieve a global vision of all the technological concepts involved in the project even if this internship is focused in satellite transmission. Section 6 describes the internship development. By means of conclusion, the new skills achieved, the knowledge applied and a professional and personal balance could be found at the end of this report.Ingeniería de TelecomunicaciónTelekomunikazio Ingeniaritz

Economically sustainable public security and emergency network exploiting a broadband communications satellite

The research contributes to work in Rapid Deployment of a National Public Security and Emergency Communications Network using Communication Satellite Broadband. Although studies in Public Security Communication networks have examined the use of communications satellite as an integral part of the Communication Infrastructure, there has not been an in-depth design analysis of an optimized regional broadband-based communication satellite in relation to the envisaged service coverage area, with little or no terrestrial last-mile telecommunications infrastructure for delivery of satellite solutions, applications and services. As such, the research provides a case study of a Nigerian Public Safety Security Communications Pilot project deployed in regions of the African continent with inadequate terrestrial last mile infrastructure and thus requiring a robust regional Communications Satellite complemented with variants of terrestrial wireless technologies to bridge the digital hiatus as a short and medium term measure apart from other strategic needs. The research not only addresses the pivotal role of a secured integrated communications Public safety network for security agencies and emergency service organizations with its potential to foster efficient information symmetry amongst their operations including during emergency and crisis management in a timely manner but demonstrates a working model of how analogue spectrum meant for Push-to-Talk (PTT) services can be re-farmed and digitalized as a “dedicated” broadband-based public communications system. The network’s sustainability can be secured by using excess capacity for the strategic commercial telecommunication needs of the state and its citizens. Utilization of scarce spectrum has been deployed for Nigeria’s Cashless policy pilot project for financial and digital inclusion. This effectively drives the universal access goals, without exclusivity, in a continent, which still remains the least wired in the world

Real-time performance analysis of a QoS based industrial embedded network

AFDX serves as a backbone network for transmission of critical avionic flows. This network is certified thanks to the WCTT analysis using Network Calculus (NC) approach. However, the pessimism introduced by NC approach often leads to an over-sized and eventually an underutilized network. The manufacturers envision to better use the available network resources by increasing occupancy rate of the AFDX network by allowing additional traffic from other critical and non-critical functions. Such harmonization of AFDX network with mixed criticality flows necessitates the use of QoS mechanism to satisfy the delay constraints in different classes of flow. In this thesis we study such QoS-aware network, in particular, based on DRR and WRR scheduling. We propose an optimal bandwidth distribution method that ensures the service required by critical flows while providing maximum service to other non-critical flows. We also propose an optimized NC approach to compute tight delay bounds. Our approach has led to computation of up to 40% tighter bounds, in an industrial AFDX configuration, as compared to the classical approach

NASA Tech Briefs, October 2001

Topics include: special coverage section on composites and plastics, electronic components and systems, software, mechanics, physical sciences, information sciences, book and reports, and a special sections of Photonics Tech Briefs and Motion Control Tech Briefs

Nascom System Development Plan: System Description, Capabilities and Plans

The NASA Communications (Nascom) System Development Plan (NSDP), reissued annually, describes the organization of Nascom, how it obtains communication services, its current systems, its relationship with other NASA centers and International Partner Agencies, some major spaceflight projects which generate significant operational communication support requirements, and major Nascom projects in various stages of development or implementation

Information Infrastructure Technology and Applications (IITA) Program: Annual K-12 Workshop

The purpose of the K-12 workshop is to stimulate a cross pollination of inter-center activity and introduce the regional centers to curing edge K-1 activities. The format of the workshop consists of project presentations, working groups, and working group reports, all contained in a three day period. The agenda is aggressive and demanding. The K-12 Education Project is a multi-center activity managed by the Information Infrastructure Technology and Applications (IITA)/K-12 Project Office at the NASA Ames Research Center (ARC). this workshop is conducted in support of executing the K-12 Education element of the IITA Project The IITA/K-12 Project funds activities that use the National Information Infrastructure (NII) (e.g., the Internet) to foster reform and restructuring in mathematics, science, computing, engineering, and technical education

Architecture de communication à QoS garantie pour la simulation distribuée

Les travaux décrits dans cette thèse s'articulent autour des architectures de communication en réseaux locaux et réseaux distants pour les applications de simulation distribuée interactive, particulièrement dans le cadre du projet Platsim. Nous avons traité dans un premier temps, les aspects gestion de la QoS pour les simulations distribuées basées sur les middlewares HLA et DDS en réseaux locaux, et ensuite nous avons étendu cette contribution avec DDS sur des réseaux grandes distances. La première contribution consiste à enrichir PlatSim par un modèle formel pour la gestion de la QoS que nous avons implémentée sur HLA pour combler les manques de QoS dont souffre ce middleware. Ensuite, nous avons proposé une architecture pour l'interconnexion des simulateurs distribués avec le middleware DDS. L'utilisation de DDS est intéressante pour la simplicité de son implémentation et ses performances de communication déjà prouvées sur des systèmes complexes. Dans la deuxième contribution, nous avons développé un algorithme de navigation à l'estime (dead-reckoning) pour l'anticipation du comportement des entités simulées. Cette approche permet d'émuler leur comportement lors de la détermination de l'erreur maximale admissible satisfaisant les contraintes de la QoS requise, ce qui, en cas de défaillance du système de communication, permet d'estimer le comportement des objets simulés. Ensuite, nous avons présenté une proposition pour l'interconnexion des simulations distribuées DDS et cette approche de dead-reckoning, par deux mécanismes différents: dans un premier temps, nous avons montré qu'il est possible d'utiliser le service de routage DDS pour mettre en place un "pont-fédéré" DDS permettant d'interconnecter des domaines DDS différents dans un même domaine IP, et ensuite nous avons proposé un "Proxy DDS" qui permet d'interconnecter des simulations DDS situées dans des domaines DDS différents et des domaines IP hétérogènes. Enfin, nos deux dernières contributions concernent l'étude et la mise en place d'une architecture de communication à grande distance à QoS garantie pour les simulations distribuées sur DDS. Tout d'abord, nous avons présenté une architecture de signalisation de la QoS pour en se basant sur l'utilisation conjointe du protocole COPS et de la signalisation SIP. Ensuite, nous avons étendu des travaux réalisés au LAAS-CNRS dans le cadre du projet européen EuQoS. Nous avons alors utilisé des composants de cette architecture que nous avons adaptés pour fournir, à l'utilisateur final ou à l'administrateur de l'application, des interfaces simples lui permettant de demander le type de service requis pour son application sans avoir besoin de changer le protocole de signalisation.Stimulated by the growth of network-based applications, middleware technologies for Distributed Interactive Simulation (DIS) applications are taking an increasing importance in large scale systems, and motivate the need to achieve end-to-end Quality-of-Service (QoS) over local and large-scale networks. The aims of this thesis revolve around network communication architecture for DIS applications in LAN and WAN. Its first contribution is to design and implement high performance Distributed Interactive Simulation (DIS) application using the HLA (High Level Architecture) and DDS (Data Distribution Service) middleware in LANs: HLA is used in conjonction with Hierarchical Timed Stream Petri Nets (HTSPN) to allow a powerful analysis techniques for validating and implementing QoS mechanisms in the application layer. Then, we show how DDS can successfully deliver the needed capabilities of DIS applications, provides fast and predictable distribution of real-time critical data in local area network. In the second contribution we suggest a novel extension of Dead Reckoning to increase the network availability and fulfill the required QoS in large-scale DIS applications. The proposed algorithm is based on a fuzzy inference system which is trained by the learning algorithm derived from the neuronal networks and fuzzy inference theory. The proposed mechanism is based on the optimization approach to calculate the error threshold violation in networking games. Then, We show the limitations of the usage DDS Routing Services over the Internet and suggests a Proxy DDS to overcome those shortcomings. In the last contributions we present a dynamic ressource allocation SIP-based framework for the signaling plane DDS-based DIS applications. We give the design and implementation of this framework, the new concepts of the extended SIP to improve the QoS management mechanisms. Then, we present an QoS approach using the EuQoS (End-to-End QoS over Heterogeneous Networks) architecture to define a NGN (Next Generation Network) architecture for distributed interactive simulation that builds, uses and manages end-to-end QoS across different administrative domains and heterogeneous networks