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Dissertations / Theses on the topic 'OSI protocol'

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Published: 5 June 2025

Last updated: 15 July 2025

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Takeuchi, Leonard Yasuhiko. "Study of OSI protocol processing engines." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30104.

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The increases in communication bandwidth provided by fiber optics and high-speed switching technologies have shifted the limiting factor in data throughput from the communication link to the communication processing. The communication processing for open systems interconnection (OSI) in particular is quite heavy due to the inclusion of data transfer syntax conversion in order to assure interoperability between different machine types. In this thesis report, two multiprocessing architectures are considered as protocol processing engines for OSI communications. The conventional approach is to have the host computer perform the protocol processing especially for the higher layers. However, the protocol processing burden at communication rates of hundreds or even thousands of million bits per second places such a heavy processing burden on the host that this becomes undesirable. The protocol processing engines act as front-end systems performing most of the OSI protocol processing, including the transfer syntax conversion, on behalf of the host. A multiprocessor approach was selected because the required amount of processing power can be supplied using lower processor technology than for an uniprocessor approach. The protocol engines were designed based on a processing model in which different packets are processed at the same time in different processors. The protocol engines are designed to perform the protocol processing for OSI layers 2 through 6. Results obtained from simulating the designs indicate that a processing throughput of a hundred megabit per second is achievable only for packets which contain very simple data structures. Applied Science, Faculty of Electrical and Computer Engineering, Department of Graduate

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Hammar, Fredrik. "Nätverksbaserade informationssystem : Standardprotokoll ANSI Z39.50/OSI SR." Thesis, Högskolan i Borås, Institutionen Biblioteks- och informationsvetenskap / Bibliotekshögskolan, 1997. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-150.

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This master thesis examines the development of the two earlier independent IR protocols Z39.50 and SR (Search and Retrieve, ISO 10162/10163), now Z39.50/SR, from the beginning of the 80s to 1996 and their functionality in the client/server environment. Z39.50 applications in library systems will allow easy access to information regardless of platform or location. The use of Z39.50 will create a new user environment. Almost all the library systems of the market support the Z39.50 and surprisingly the use of it in Sweden lied on a very low leve! in 1996. This thesis was followed-up by an interview and a questioner among the Swedish Z39.50 users. They could see a huge potential of development concerning the future IR process. Z39.50 will change the libraries' traditional IR structure and the behaviour of the end-users.

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Aboul, Hamid I. "Temporal modelling of an OSI-based communications protocol." Thesis, Swansea University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.635841.

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A central issue in significantly large industrial distributed computer control systems, but one largely ignored by systems designers, is the question of the real-time handling of data. Recently, though, it has become evident that many installed systems are not able to meet the requirements of full plant-wide integration and synchronization. It is becoming clear that future distributed control systems will only be capable of performing the very exacting tasks asked of them if they are supported by an inherently time-conscious communication system, together with an ability to handle data from a variety of different computer-based devices, in a cohesive fashion. A glimmer of hope appeared with the General Motors-inspired MAP initiative. Although a milestone in providing standardized computer interconnection, MAP does not adequately address the all-important issue of real time. When this issue is, however, fully understood, it is found that it invades all aspects of systems design, where a primary requirement is for the totally deterministic handling of data - both in transmitting the data and in processing it. As a consequence, in the development of an industrial communications system, all supporting components must be carefully designed to ensure completely predictable performance. This thesis tackles the design issue in the particular context of communication protocols. The thesis postulates that it is vital to design protocols which are not only logically incorrect, but also have a fully defined temporal behaviour. The question then becomes one of identifying suitable tools for use in the specification, design and verification of protocols - both logically and in the time-domain.

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Kou, Tian. "Conformance testing of OSI protocols : the class O transport protocol as an example." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26427.

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This thesis addresses the problem of conformance testing of communication protocol implementations. Test sequence generation techniques for finite state machines (FSM) have been developed to solve the problem of high costs of an exhaustive test. These techniques also guarantee a complete coverage of an implementation in terms of state transitions and output functions, and therefore provide a sound test of the implementation under test. In this thesis, we have modified and applied three test sequence generation techniques on the class 0 transport protocol. A local tester and executable test sequences for the ISO class 0 transport protocol have been developed on a portable protocol tester to demonstrate the practicality of the test methods and test methodologies. The local test is achieved by an upper tester residing on top of the implementation under test (IUT) and a lower tester residing at the bottom of the IUT. Tests are designed based on the state diagram of an IUT. Some methodologies of parameter variations have also been used to test primitive parameters of the implementation. Some problems encountered during the implementation of the testers and how they are resolved are also discussed in the thesis. Science, Faculty of Computer Science, Department of Graduate

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Chen, Yan. "Traitement transactionnel dans un environnement OSI." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376126461.

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Lasorso, Daniel. "Watershed Security Telemetry Network Protocol for Reliability Assurance." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1258576929.

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Andrey, Laurent. "Protocoles de communication et grammaires attribuées." Nancy 1, 1993. http://www.theses.fr/1993NAN10083.

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Le but de l'étude est d'examiner l'adéquation des grammaires attribuées pour décrire formellement des protocoles de communication et pour en dériver quasi-automatiquement une implantation d'une entité de protocole. Les protocoles considérés sont ceux des couches basses du modèle OSI, et l'utilité de telles descriptions formelles est placée dans le contexte général de l'ingénierie des protocoles. La contribution personnelle consiste en une proposition du formalisme GAPP (grammaires attribuées pour les protocoles) basée sur les travaux existants en intégrant des idées issues des applications traditionnelles des grammaires attribuées en compilation. Dans GAPP, les règles de production servent à décrire la partie contrôle d'un protocole. Les terminaux représentent les interactions (primitives de service, unîtes de donnée, time-out) qu'échange le protocole avec l'extérieur. Les attributs permettent de relier les interactions entre elles, et d'incorporer le contexte dans la grammaire par l'intermédiaire de gardes sur les productions. L'exemple normalisé abracadabra est traité. Des extensions comme le multiplexage sont abordées

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Van, Wyk Jacobus Leendert. "Comparing network coding implementations on different OSI layers / Jacobus Leendert van Wyk." Thesis, North-West University, 2010. http://hdl.handle.net/10394/8430.

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Network coding is a technique used to increase the capacity of a network by combining messages sent over the network. The combined messages could be separated by using sufficient original messages which were used to combine the messages. Network coding can be implemented in different layers of the 051 stack, but to date a complete comparison between different implementations of network coding has not been done. The goal of this dissertation is to implement a wireless node model with network coding in the MAC layer and evaluate the performance characteristics of reference networks that implement the new node model. This will serve as the first step of a greater goal, namely finding the most favourable position in the 051 stack to implement network coding. The characteristics of the different implementations of network coding are presented in this dissertation. Simulations were done in OPNET® to find further attributes concerning the implementation of network coding in the MAC layer. The simulation process used is presented and explained, and the results from the simulations are analysed. Network coding in the simulations was implemented opportunistically. The results show that the more often different nodes send frames to the coding node, the better network coding performs. The work contributes to finding the best layer for implementing network coding for its increased throughput. A benchmark network was created so that network coding could be implemented in all the layers of the 051 stack, and then be compared to each other. An implementation of network coding in the MAC layer was simulated and analyzed. We conclude that, because there are so many different purposes for which networks are used, a single instance of network coding is unlikely to be similarly beneficial to all purposes. There still remains work to find the most favourable position for network coding in the 051 stack for all the different types of network coding. Thesis (M. Ing. (Computer and Electronical Engineering))--North-West University, Potchefstroom Campus, 2011

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Bert, Denis. "Systemes d'annuaire osi : specifications de mise en oeuvre pour la messagerie et l'administration de reseau." Paris 6, 1988. http://www.theses.fr/1988PA066075.

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Etude et specification de l'utilisation des systemes d'annuaire pour l'adressage des systemes osi, l'administration de reseau et la messagerie electronique. Les modeles, services et protocoles des systemes d'annuaire osi definis par la nouvelle serie de recommandations ccitt x500 sont exposes. Sont ensuite decrits les mecanismes de consultation annuaire permettant, a partir d'un nom d'application ou d'une adresse reseau, de determiner les elements d'adressage application ou les informations de routage reseau

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Pirkl, Tomáš. "Web server pro vestavěné aplikace." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2007. http://www.nusl.cz/ntk/nusl-412774.

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This work discuses Embedded Ethernet systems. Embedded Webserver Platform is designed. This design embrace microkontroler, Ethernet driver, and external SRAM. It includes implementation on PCB with MMC interface and software implementation of MMC driver and FAT file system. Reference model ISO/OSI, reference model TCP/IP, Ethernet and UDP, TCP, IP, HTTP protocol is presented.

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Šoustar, Jiří. "Modul rozhraní Ethernet pro platformu FITkit." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2008. http://www.nusl.cz/ntk/nusl-235428.

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This graduation thesis is aimed at design and implementation of embedded systems, network communication and support of the network communication for embedded systems. Furthermore it introduces school platform FITkit and offers a conceptional extension of the network interface for this platform based on Ethernet network standard. Based on that conception I'm trying to find and describe suitable solution for FITkit platform which realizes a network interface as a form of extension module capable of development supporting.

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Hagström, Jesper, and Lukas Lindblom. "Performance of Network and Transport Protocols in the Implementation of a New Cryptocurrency." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-240985.

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It has been suggested that some cryptocurrencies have potential to take the role as a global digital payment system. However, as the current technology stands, all cryptocurrencies have shortcomings which are growing when scaling parameters. This emphasizes the importance of fast and reliable data transmissions when implementing network protocols to handle the transactions. However, little research has been conducted to specifically support the development of cryptocurrencies regarding protocol performance comparison. This study will be assisting the development of a new cryptocurrency, proposed by HAJ Enterprise. The report uses a theoretical framework of economic perspectives to investigate if the proposed cryptocurrency could take the role as a form of good money. Furthermore, the main purpose of the study is to identify which existing transport protocol with appurtenant parameters would be the most suitable in an implementation of the proposed cryptocurrency. To answer these questions, the study measures latency, throughput and reliability of protocols in a test simulating a real case of long distance data transmission. These results are then compared to findings from similar studies. From the results, it was suggested that proposed cryptocurrency satisfies the requirements of good money, as intrinsic value was found through the monetary policy. Moreover, it was found that TCP IPv6 showed the best performance regarding data transmission. However, considering the current state of the IPv6 adoption rate into consideration, it is suggested that TCP IPv4 with a packet size in the range of 1024-2048 would be beneficial. Further research in different settings is required for more nuanced results. Det har föreslagits att kryptovalutor har potential att fungera som ett globalt digitalt betalmedel. Den bakomliggande tekniken medför dock att alla kryptovalutor har brister. Dessa brister är växande när parametrar skalas upp. Detta understryker vikten av snabba och pålitliga överföringar av data och passande val vid implementering av protokoll för att hantera transaktionerna. Forskning inom området för effektiv dataöverföring inom kryptovalutor tillåter fler möjligheter i betraktande av lösningar till storskaliga nätverk. Dessvärre har en begränsad mängd forskning bedrivits som specifikt understödjer utvecklingen av kryptovalutor genom jämförelse av protokollprestanda. Denna studie medverkar i utvecklingen av en ny kryptovaluta, föreslagen av HAJ Enterprise. Rapporten använder ett teoretiskt ramverk av ekonomiska perspektiv på kryptovalutor för att undersöka om den föreslagna kryptovalutan kan klassas som good money. Vidare är det huvudsakliga syftet med studien att identifiera vilka befintliga transportprotokoll, med tillhörande parametrar, som skulle vara mest lämpade att implementera i den föreslagna kryptovalutan. För att besvara dessa frågor mäts fördröjning, genomströmning och tillförlitlighet av protokoll i en testmiljö som simulerar ett verkligt fall med dataöverföring mellan långa avstånd. Dessa resultat jämförs därefter med resultat från liknande studier. Från resultaten kunde rapporten visa att den föreslagna kryptovalutan kan klassificeras som en form av pengar, då inneboende värde kunde identifieras genom kryptovalutans monetära policy. Det var också visat att TCP IPv6 hade bäst prestanda gällande dataöverföring. Men med hänsyn till den globala etablering av IPv6 föreslås TCP IPv4 med en paketstorlek inom en räckvidd mellan 1024 till 2048 byte som mest fördelaktig. Fortsatt forskning inom området och utökade tester inom olika miljöer krävs för ett mer nyanserat resultat.

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Lo, Jeffrey Kin Hung. "Open systems interconnection passive monitor OSI-PM." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29418.

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The Open Systems Interconnection Passive Monitor (OSI-PM), which is based on the principles of the OSI-Reference Model (OSI-RM), provides a framework for the development of multi-layer passive monitoring and testing. It adopts the same seven-layer architecture of the OSI-RM and provides the capability of selectively displaying, capturing, and analyzing the protocol events on single or multiple connections for any subset or all of the seven layers. Different from conventional monitors, the OSI-PM is able to detect protocol violation as they occur in addition to the monitoring functions. The current OSI-PM is able to monitor and test up to the transport layer of the OSI-RM. This thesis discusses the design, prototype implementation and testing of the OSI-PM. Science, Faculty of Computer Science, Department of Graduate

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Strachan, Rebecca Mary. "Development of performance criteria for OSI protocols." Thesis, Leeds Beckett University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293872.

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Zhang, Bairong. "Formal specification and verification of OSI protocols." Thesis, University of Bristol, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337284.

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Chraïbi, Chakib. "Contribution au test de protocoles OSI." Bordeaux 1, 1987. http://www.theses.fr/1987BOR10553.

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Mise en oeuvre d'un test de protocoles de communications osi. La methodologie de test developpee est basee sur le systeme de test reparti. Etude de la faisabilite du systeme et creation d'un langage permettant la mise au point du test

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Chraïbi, Chakib. "Contribution au test de protocoles OSI." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37603984f.

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Muharish, Essa Yahya M. "PACKET FILTER APPROACH TO DETECT DENIAL OF SERVICE ATTACKS." CSUSB ScholarWorks, 2016. https://scholarworks.lib.csusb.edu/etd/342.

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Denial of service attacks (DoS) are a common threat to many online services. These attacks aim to overcome the availability of an online service with massive traffic from multiple sources. By spoofing legitimate users, an attacker floods a target system with a high quantity of packets or connections to crash its network resources, bandwidth, equipment, or servers. Packet filtering methods are the most known way to prevent these attacks via identifying and blocking the spoofed attack from reaching its target. In this project, the extent of the DoS attacks problem and attempts to prevent it are explored. The attacks categories and existing countermeasures based on preventing, detecting, and responding are reviewed. Henceforward, a neural network learning algorithms and statistical analysis are utilized into the designing of our proposed packet filtering system.

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Wvong, Russil. "A new methodology for OSI conformance testing based on trace analysis." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29343.

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This thesis discusses the problems of the conventional ISO 9646 methodology for OSI conformance testing, and proposes a new methodology based on trace analysis. In the proposed methodology, a trace analyzer is used to determine whether the observed behavior of the implementation under test is valid or invalid. This simplifies test cases dramatically, since they now need only specify the expected behavior of the IUT; unexpected behavior is checked by the trace analyzer. Test suites become correspondingly smaller. Because of this reduction in size and complexity, errors in test suites can be found and corrected far more easily. As a result, the reliability and the usefulness of the conformance testing process are greatly enhanced. In order to apply the proposed methodology, trace analyzers are needed. Existing trace analyzers are examined, and found to be unsuitable for OSI conformance testing. A family of new trace analysis algorithms is presented and proved. To verify the feasibility of the proposed methodology, and to demonstrate its benefits, it is applied to a particular protocol, the LAPB protocol specified by ISO 7776. The design and implementation of a trace analyzer for LAPB are described. The conventional ISO 8882-2 test suite for LAPB, when rewritten to specify only the expected behavior of the IUT, is found to be more than an order of magnitude smaller. Science, Faculty of Computer Science, Department of Graduate

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Thai, Kim-Loan. "Analyse de performances de protocoles de transport : application a tp4 osi." Paris 6, 1990. http://www.theses.fr/1990PA066335.

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L'analyse et la conception de protocoles de communication se heurtent a des problemes de performance. Ces derniers sont mis en avant par la complexite et l'heterogeneite croissante des reseaux sous-jacents. Il devient plus que jamais necessaire de disposer de protocoles performants et de techniques de controle efficaces, surtout au niveau transport. La normalisation laisse une pour le protocole de transport osi classe 4 une tres grande latitude d'implantation. Nous proposons et evaluons differentes strategies d'implantation pour les mecanismes de controle d'erreur et de flux et de gestion des acquittements et du desequencement. Leur influence et celle des valeurs de parametres sur les performances du protocole sont etudiees par simulation. De cette analyse sont degagees des regles heuristiques guidant le dimensionnement en fonction de l'environnement du protocole et de la connaissance qu'en a le developpeur. Le delai de reexpedition et la taille de fenetre apparaissant comme les facteurs-cle, nous developpons un modele analytique les prenant en compte simultanement et permettant d'optimiser les criteres de performance dans un environnement reseau donne. Par ailleurs, nous presentons et discutons l'evolution actuelle des protocoles de transport, en particulier, vers les reseaux a hauts debits

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Bonet, d'Oléon Karen de. "Spécification et validation du protocole de communication KerNet+." Nantes, 1991. http://www.theses.fr/1991NANT2066.

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L'objet du travail présenté ici consiste en la spécification complète d'un protocole de communication, appelé KerNet+, de la couche Application du modèle de référence normalisé par l'ISO pour l'Interconnexion des Systèmes Ouverts. Ce protocole introduit et définit un ensemble de services de communication, mis directement à la disposition des tâches utilisateur des sites communicants et conçus pour s'appliquer spécifiquement aux tâches de conduite et de pilotage en temps réel de procédés industriels continus et manufacturiers complexes. Les hypothèses adoptées pour spécifier le protocole KerNet+ sont que ses services sont destinés à des tâches parallèles, asynchrones et faiblement couplées. La principe de communication de KerNet+ repose sur la coopération par échange de messages et le mode de communication choisi est une extension des concepts de CSP, c'est-à-dire le mode synchrone par rendez-vous, dont on propose une décomposition en deux phases génériques. Il est montré que cette décomposition autorise l'écriture naturelle de synchronisations réputées complexes dans les applications temps réel. Il est proposé une architecture du protocole conforme à la norme ISO 9545 de l'ISO et le protocole est modélisé sous la forme de cinq systèmes de transition parallèles synchronisés. Cette architecture autorise l'utilisation des services de KerNet+ tant dans un contexte réparti que pour faire interagir des tâches résidant sur le même site, la localisation effective des tâches restant transparente à l'utilisateur. Le chapitre 1 est consacré à la présentation du langage CSP et des multiples extensions qui en ont découlé. Le chapitre 2 contient la description des services de communication introduits dans le protocole KerNet+. Le Chapitre 3 propose une structuration des entités fonctionnelles chargées de la réalisation des services de KerNet+ et modélise leur comportement. Le Chapitre 4 présente une spécification formelle du protocole dans le langage normalisé Estelle et son comportement global est vérifié par observation en simulation.

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Haj, Houssain Samer Mazaré Guy Mossière Jacques. "DOSIS un serveur OSI pour l'ouverture des systèmes distribués au monde extérieur /." S.l. : Université Grenoble 1, 2008. http://tel.archives-ouvertes.fr/tel-00328632.

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Dakroury, Yasser. "Spécification et validation d'un protocole de messagerie multi-serveur pour l'environnement MMS." Nantes, 1990. http://www.theses.fr/1990NANT2041.

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On présente un nouveau concept pour l’implémentation du protocole MMS: le protocole de multi-serveur. De sa définition, le protocole multi-serveur MMS envisage une coopération possible entre plusieurs serveurs MMS pour exécuter un service demandé par l'utilisateur client. Ce protocole de multi-serveur nécessite la définition d'un nouveau type d'objet, c'est-à-dire l'objet reparti. Une architecture générale a été introduite pour présenter les interactions possibles entre l'utilisateur client et les serveurs, dits principal et secondaire(s). Cette architecture repose sur le fait que l'objet est considéré comme un agent actif qui peut communiquer avec la fonction opératoire du serveur. L'objet liste de variables et l'objet tache ont été choisis pour être traités par ce protocole de multi-serveur. Les spécifications du protocole sont présentées par des automates d'états finis. Ensuite, ces automates ont été validés à l'aide du système auto en utilisant les algèbres de processus communicants.

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OLIVEIRA, Renan Rodrigues de. "Recuperação Contextualizada de Documentos Integrados pelo Protocolo OAI-PMH." Universidade Federal de Goiás, 2010. http://repositorio.bc.ufg.br/tede/handle/tde/532.

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Made available in DSpace on 2014-07-29T14:57:53Z (GMT). No. of bitstreams: 1 Renan Rodrigues 1.pdf: 1818012 bytes, checksum: b12a88acdfeb11f473ab5b1087c11311 (MD5) Previous issue date: 2010-04-09 This work focuses on two aspects: the integration of a set of digital libraries, repositories and other data providers through the OAI-PMH protocol (Open Archives Initiative Protocol for Metadata Harvesting) and contextualized documents retrieval in this integrated repository. It is proposed the use of ontologies and content analysis of articles in wiki environments in the context definition. The interest in ontologies is in its use as artifacts of specification domain. An ontology is a data model that represents a set of concepts and their relationships within a domain of knowledge. A wiki is a collaborative environment, containing a collection of items connected by hyperlinks, which can be edited collectively by using a web browser. In this work, the wiki environments are used as an auxiliary repository of knowledge to the extraction of relevant terms. Thus, several concepts and relationships that may not be present in the ontology that specifies the domain of knowledge (since the construction of ontologies is a complex process) can be identified. The result of the developed tool processing is a ranking of documents ordered by a higher degree of importance with respect to the query provided by a user and a particular domain of knowledge, which is specified by an ontology. Este trabalho aborda duas vertentes: a integração de um conjunto de bibliotecas digitais, repositórios e outros provedores de dados por meio do protocolo OAI-PMH (Open Archives Initiative Protocol for Metadata Harvesting) e a recuperação contextualizada de documentos neste repositório integrado. Propõe-se a definição dos contextos utilizando ontologias e a análise do conteúdo de artigos de ambientes wiki. O interesse em ontologias está no seu uso como artefatos de especificação de domínios. Uma ontologia é um modelo de dados que representa um conjunto de conceitos e seus relacionamentos, dentro de um domínio de conhecimento. Um wiki é um ambiente colaborativo, que contêm uma coleção de artigos conectados através de hiperlinks, que podem ser editados coletivamente, através da utilização de um navegador web. Neste trabalho, os ambientes wiki são utilizados como um repositório de conhecimento auxiliar, para a extração de termos relevantes. Dessa forma, diversos conceitos e relacionamentos que podem não estar presentes na ontologia que especifica o domínio de conhecimento (uma vez que a construção de ontologias é um processo complexo) podem ser identificados. O resultado do processamento da ferramenta desenvolvida é um ranking de documentos ordenado por maior grau de relevância com relação à consulta fornecida por um usuário e a um determinado domínio de conhecimento, que é especificado por uma ontologia.

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Haj, Houssain Samer. "Dosis : un serveur OSI pour l'ouverture des systèmes distribués au monde extérieur." Grenoble INPG, 1988. http://tel.archives-ouvertes.fr/tel-00328632/.

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L'ouverture de ces systèmes est assurée au moyen d'un service de communication externe. Ce service permet aux applications s'exécutant dans le système distribue local de communiquer à plusieurs niveaux de protocoles avec d'autres applications s'exécutant sur des systèmes distants distribues ou centralises. On étudie l'architecture et le fonctionnement de tels systèmes

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Otčenášek, Martin. "Distribuované řídící systémy a jejich využití v praxi." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217601.

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In control technique there is evident highly expressive trend of shifting from efficient central managing systems towards smaller systems which are distributed on technology and which are connected by communication bus. There is no need to link all signals to central management system, operation is then distributed and realized directly in individual parts of technology. That’s why these systems are called distributive managing systems. Distributive managing systems are widely used not only in industrial applications but also in buildings, cars, etc..

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Dupeux, Arnaud. "Spécification et implantation de protocoles OSI : une expérience de la couche transport dans le langage ADA." Bordeaux 1, 1986. http://www.theses.fr/1986BOR10527.

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Validation des protocoles, amelioration des algorithmes existants. Specification et description detaillees d'une entite de transport osi, gestion des conflits et des evenements, proposition d'un modele. Langage ada et ses possibilites pour exprimer des phenomenes paralleles; application: programmation de l'architecture de la couche transport osi

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Wang, Jun. "Vidi: a Lightweight Protocol Between Visualization Systems and Digital Libraries." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/33845.

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Achieving interoperability between digital libraries and visualization tools is a difficult problem. To solve this problem, a version of the Open Archives Initiative (OAI) Protocol for Metadata Harvesting called VIDI is proposed. It is a lightweight protocol, which contains only 5 request verbs -- Identify, ListMetadataFormats, ListVisdataFormats, ListTransformers, and RequestResultSet. It is extended from the OAI protocol, which enables its simplicity and wider acceptability. It is flexible, which avoids a rigid architecture in implementation. It is general, so it can apply to all kinds of Visualization Systems and Digital Libraries. But most importantly, it reaches our goal of enabling operability between Visualization Systems and Digital Libraries. The protocol design and implementation details are given. Two prototype systems are implemented to demonstrate the above features. Implementation details are given about ENVISION-ODL and ENVISION-MARIAN. Analysis, evaluation, and conclusions reinforce the discussion of the benefits of VIDI. Master of Science

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Jacinto, Montes Ricardo R. "Protocoles de validation à deux phases dans les systèmes transactionnels répartis : spécification, modélisation et vérification." Toulouse 3, 1995. http://www.theses.fr/1995TOU30050.

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Assurer la coherence des donnees dans un traitement reparti est un probleme majeur qui a besoin, pour etre resolu, de la definition des regles de fonctionnement precises. Dans ce contexte, l'osi a defini le protocole iso-tp (transaction processing) pour la realisation des traitements transactionnels repartis. Iso-tp est un protocole a controle centralise base sur une structure hierarchique arborescente qui s'appuie sur la fonction ccr (commitment concurrency & recovery) afin d'assurer la coherence des relations bipoint qui composent l'arbre transactionnel. Pour maitriser la complexite des mecanismes specifies dans iso-tp, nous avons defini une methodologie de modelisation et verification structuree fondee sur la decomposition (recursive) d'un systeme en sous-systemes et sur les niveaux d'abstraction. Le protocole iso-tp est tres bien adapte pour les applications tels que les systemes de gestion de bases de donnees repartis (sgbdr). Cependant le couplage des mecanismes de iso-tp et du sgbdr fait ressortir une complexite qui, pour etre maitrisee, necessite d'une methodologie de conception. Dans ce but une methodologie fondee sur la complementarite de deux techniques de description formelle (reseaux predicat/transition etiquetes et estelle) a ete developpee pour guider la conception d'un sgbdr reel. La constante evolution technologique conduit au developpement d'applications qui s'appuient sur le concept de travail cooperatif. Ce type d'applications induit de nouveaux besoins en termes de protocoles de validation. Pour repondre a ces besoins un protocole fonde sur les concepts d'initiation repartie et de coordonnateur dynamique a ete defini. Ce protocole permet d'assurer: l'adaptation a toute topologie de travail, l'independance par rapport a un site particulier et la diminution du temps de validation

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José, de Menezes Cardoso Junior Marcos. "Clio-i: Interoperabilidade entre repositórios digitais utilizando o protocolo OAI-PMH." Universidade Federal de Pernambuco, 2007. https://repositorio.ufpe.br/handle/123456789/2673.

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Made available in DSpace on 2014-06-12T16:00:06Z (GMT). No. of bitstreams: 2 arquivo6016_1.pdf: 2591725 bytes, checksum: 2af65bc5a065dfd598a2058423fac02c (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior O interesse na criação de Bibliotecas Digitais cresceu significativamente a partir do sur- gimento e da disseminação da Web, que trouxe consigo a necessidade de ferramentas que facilitassem a publica»c~ao, gerenciamento e a recupera»c~ao da informa»c~ao digital. Atual- mente, podemos observar uma ampla gama de Bibliotecas Digitais, que se caracterizam como servi»cos que gerenciam e disponibilizam documentos digitais, de forma mais es- truturada do que convencionalmente se observa na Web. Nesses servi»cos, em geral, os documentos s~ao descritos por metadados, recuperados atrav¶es de ferramentas de busca estruturada e visualizados em interfaces apropriadas.Uma das limita»c~oes de grande parte das Bibliotecas Digitais existentes ¶e a aus^encia de mecanismos de integra»c~ao de dados, de maneira a fornecer ao usu¶ario, acesso uni¯cado e transparente aos reposit¶orios gerenciados por diferentes servi»cos. Esse problema ¶e conhecido na literatura como o problema da Inte- roperabilidade entre Bibliotecas Digitais. Dentro desse contexto, desenvolvemos o Clio-i, um sistema para gerenciamento de Bibliotecas Digitais. A sua arquitetura apresenta ca- racter¶³sticas desej¶aveis como um m¶odulo de recupera»c~ao de documentos, um visualizador de documentos e dois m¶odulos para interoperabilidade entre reposit¶orios digitais. Para prover o mecanismo de interoperabilidade, foi implementada no Clio-i uma extens~ao do protocolo OAI-PMH (Open Archives Initiative-Protocol for Metadata Harvesting), que ¶e um padr~ao internacional para interoperabilidade de reposit¶orios digitais. A interopera- bilidade do Clio-i ¶e composto por dois m¶odulos: (1) o Clio-i Data Provider, respons¶avel por exportar os metadados dos documentos gerenciados localmente, de acordo com os padr~oes estabelecidos no OAI-PMH; e (2) o Clio-i Service Provider, que realiza a coleta de informa»c~oes a partir de qualquer provedor de dados remoto baseado em OAI-PMH. O prot¶otipo de sistema implementado foi validado em dois estudos de caso, operacionali- zando centenas de milhares de registros e efetivando a extens~ao do protocolo OAI-PMH adotada

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Azeem, Muhammad Moazam. "Erasure Correcting Codes for Opportunistic Spectrum Access (OSA)." Thesis, Paris, CNAM, 2014. http://www.theses.fr/2014CNAM1002/document.

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Les années récentes ont vu l’explosion du trafic sur les réseaux mobiles depuis l’apparition de nouveaux terminaux (smartphones, tablettes) et des usages qu’ils permettent, en particulier les données multimédia, le trafic voix restant sensiblement constant. Une conséquence est le besoin de plus de spectre, ou la nécessité de mieux utiliser le spectre déjà alloué. Comme il n’y a pas de coordination entre les utilisateurs secondaire(s) et primaire, avant toute transmission les premiers doivent mettre en œuvre des traitements pour détecter les périodes dans lesquelles l’utilisateur primaire transmet, ce qui est le scénario considéré dans cette thèse. Nous considérons donc une autre approche, reposant sur l’utilisation de codes correcteurs d’effacements en mode paquet. La dernière partie de la thèse aborde un scénario dans lequel il n’y a plus d’utilisateur primaire, tous les utilisateurs ayant le même droit à transmettre dans le canal. Nous décrivons une modification de la couche MAC du 802.11 consistant à réduire les différents temps consacrés à attendre (SIFS, DIFS, backoff, . . .) afin d’accéder plus souvent au canal, au prix de quelques collisions supplémentaires qu’il est possible de récupérer en mettant en œuvre des codes correcteurs d’effacements The emergence of new devices especially the smartphones and tablets having a lot of new applications have rocketed the wireless traffic in recent years and this is the cause of main surge in the demand of radio spectrum. There is a need of either more spectrum or to use existing spectrum more efficiently due to dramatic increase in the demand of limited spectrum. Among the new dynamic access schemes designed to use the spectrum more efficiently opportunistic spectrum access (OSA) is currently addressed when one or more secondary users (SU) are allowed to access the channel when the PU is not transmitting. The erasure correcting codes are therefore envisioned to recover the lost data due to sensing impairments. We define the parameter efficiency of SU and optimize it in-terms of spectrum utilization keeping into account sensing impairments, code parameters and the activity of PU. Finally, the spectrum access for multiple secondary users is addressed when there is no primary and each user has equal right to access the channel. The interesting scenarios are Cognitive radio networks and WiFi where 802.11 protocol gives the specification for MAC layer. The throughput curvesachieved by retransmission and using various erasure correcting codes are compared. This modification in MAC layer will reduce the long waiting time to access the channel, as the number of users are increased

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Azeem, Muhammad Moazam. "Erasure Correcting Codes for Opportunistic Spectrum Access (OSA)." Electronic Thesis or Diss., Paris, CNAM, 2014. http://www.theses.fr/2014CNAM1002.

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Nascimento, Júnior Hélio Martins do. "Sistema de recomendação hídrido para bibliotecas digitais que suportam o protocolo OAI PMH." Universidade Federal de Alagoas, 2008. http://repositorio.ufal.br/handle/riufal/826.

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The growth of Web technologies has benefited researchers and the academic community by supporting the access of electronic publications as soon as they have been finished and published. In this context, Digital Libraries emerges as complex information systems which are essential for disseminating and preserving data, information and knowledge. However, due to the high amount of content available on the Web, specially in Digital Libraries, users face many correlated options, what result in the phenomenon known as information overload. Aiming to decrease or even eliminate these diffculties, recommender systems for Digital Libraries have been proposed and developed. This work presents a personalized recommender system which presents alternative ways to achieve better query results. For this, the main existing approaches of automatic recommendation have been studied in order to identify extension points and points to be improved. The proposed recommender system follows a hybrid approach which combines filtering techniques, content-based recommendation and collaborative recommendation. A hybrid recommendation engine has been proposed, which uses standard technologies for content description (Dublin Core), for communication with Digital Libraries (OAI-PMH Protocol ), as well as the user profile extracted from the curriculum vitae Lattes. The proposed solution has been evaluated in the context of the CiteSeer database, which contains papers and articles in the Dublin Core format. The preliminary results has showed an improvement in the quality of recommendation, thus presenting a better precision and coverage, when compared with existing approaches based either on content-based recommendation or on collaborative recommendation O crescimento acelerado das tecnologias Web tem beneficiado pesquisadores e acadêmicos, pois as publicações de pesquisa podem ser acessadas eletronicamente tão logo elas tenham sido finalizadas e publicadas. Nesse contexto, surgem as Bibliotecas Digitais como um sistema de informação complexo que possui uma série de atividades que integram coleções, serviços e pessoas em suporte ao completo ciclo de criação, disseminação, acesso e preservação de dados, informação e conhecimento. No entanto, devido a enorme quantidade de conteúdo presente na Web, em particular nas Bibliotecas Digitais, usuários acabam se deparando com uma diversidade muito grande de opções, o que leva ao fenômeno conhecido como sobrecarga de informação. Com o objetivo de contribuir para amenizar ou até mesmo eliminar essas dificuldades, sistemas de recomendação para Bibliotecas Digitais têm sido propostos e desenvolvidos. Este trabalho segue essa direção, investigando soluções alternativas para alcançar mais qualidade nas indicações geradas por um sistema de recomendação na sua tarefa de ajudar os seus usuários. Para isso estudou-se as abordagens tratadas na literatura especializada sobre tais sistemas, propondo-se em seguida, um sistema de recomendação personalizada de artigos científicos para Bibliotecas Digitais. Tal sistema seguiu uma abordagem híbrida, procurando tirar proveito das características interessantes identificadas nas técnicas de filtragem e recomendação baseadas em conteúdo e colaborativa. Nesse sentido desenvolveu-se um engenho de recomendação híbrido que se utiliza de tecnologias padrão para a descrição de conteúdo (Padrão Dublin Core), comunicação com Bibliotecas Digitais (Protocolo OAI-PMH) e perfil do pesquisador (Currículo Lattes). Finalmente, avaliou-se o sistema proposto sobre uma base de dados do CiteSeer contendo artigos no formato Dublin Core, tendo os resultados preliminares mostrado-se satisfatórios melhorando a precisão na recomendação e a cobertura quando comparado com sistemas que implementam abordagens baseada em conteúdo e colaborativa isoladamente

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Ayoub, Dit Ayadi Mohamed. "Contribution à la spécification formelle et vérification d'architectures de communication pour les transactions distribuées (couches hautes du modèle de référence OSI DE L'ISO)." Toulouse 3, 1990. http://www.theses.fr/1990TOU30118.

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Les travaux presentes dans ce memoire portent sur la specification formelle et l'analyse des mecanismes commitment concurrency recovery (ccr) et transaction processing (tp) de la couche application du modele osi de l'iso pour les reseaux d'ordinateurs. Ces mecanismes permettent la realisation d'actions atomiques sur des liaisons bipoints (ccr) et dans un contexte arborescent (tp). Deux techniques complementaires de description formelle sont utilisees: le modele reseaux de petri etiquete (rpte) et le langage estelle. La modelisation de la fonction ccr au moyen du modele rpte a montre en particulier, la necessite, d'une part, de specifier une phase dite d'initialisation de la relation ccr (distribution dynamique des roles superieur et subordonne) et, d'autre part, de definir une nouvelle primitive de service. La specification au moyen du langage estelle d'une architecture transactionnelle a montre, en particulier, l'interet de ce langage pour la specification d'une architecture complexe (comportant cinq niveaux de fonctionnalites du modele osi de l'iso: presentation - ccr ase - tp ase - sacf-macf)

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KOWATA, Elisabete Tomomi. "Metadados de Bancos de Dados Relacionais: Extração e Exposição com o Protocolo OAI-PMH." Universidade Federal de Goiás, 2011. http://repositorio.bc.ufg.br/tede/handle/tde/517.

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Made available in DSpace on 2014-07-29T14:57:50Z (GMT). No. of bitstreams: 1 Dissertacao Elisabete T Kowata.pdf: 2397519 bytes, checksum: df1ed4bd74a16c5e66a0ff4d7f8f9825 (MD5) Previous issue date: 2011-09-11 Information about a particular subject can be stored in different repositories such as databases, digital libraries, spreadsheets, text files, web pages etc. In this context of heterogeneous data sources, to query, possibly in natural language, to integrate information and to promote interoperability are tasks that depend, among other factors, on the prior knowledge that an user has regarding location, owner, content description of each information source etc. More specifically, in the case of database, this information are not usually stored in a catalogue of the database management system and to obtain is necessary to resort to the administrator s knowledge database. Another factor is the absence of search engines to databases in the web that access and make available the information in those repositories, data are limited due to the organizations themselves. In a shared information environment, it is highly relevant to make possible access to metadata that describe a data source, regardlessly of the device and format in which is stored. This study aims to describe a mechanism to promote interoperability of relational databases with other sources of information through the extraction and exposing of metadata using OAI-PMH Informações sobre um determinado assunto podem estar armazenadas em diferentes repositórios como banco de dados, bibliotecas digitais, planilhas eletrônicas, arquivos textos, páginas na web etc. Nesse contexto de fontes de dados heterogêneas, consultar, possivelmente em linguagem natural, integrar informações e promover interoperabilidade são tarefas que dependem, dentre outros fatores, do conhecimento prévio que um usuário tem sobre a localização, o proprietário, a descrição do conteúdo de cada fonte de informação. Mais especificamente, no caso de bancos de dados, essas informações não são, em geral, armazenadas no catálogo de um sistema gerenciador de bancos de dados; para obtê-las é necessário recorrer ao conhecimento do administrador desse banco. Outro fator que evidencia essa dependência é a ausência de mecanismos de busca a bancos de dados na web que acessam e tornam disponíveis as informações contidas nesses repositórios, devido ao fato desses dados estarem limitados às próprias organizações. Em um ambiente de compartilhamento de informações, é altamente relevante tornar possível o acesso aos metadados que descrevem uma fonte de dados, independentemente do meio e do formato em que esteja armazenada. Este trabalho tem como objetivo descrever um mecanismo para promover interoperabilidade de bancos de dados relacionais com outras fontes de informações, por meio da extração e exposição dos metadados usando o protocolo OAI-PMH.

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Léon, Jacques. "Conception et réalisation d'un système de transfert de fichiers fondé sur le protocole de fichier virtuel FTAM (ISO) et application à la transmission de données par le satellite TELECOM 1 entre le CERN et Saclay." Paris 11, 1985. http://www.theses.fr/1985PA112252.

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Le File Transfer System (ou FTS) est un logiciel de transfert de fichier conforme au modèle de référence ISO. Il recouvre les fonctions du protocole de fichier virtuel FTAM, et de la couche présentation. Il a été conçu pour interconnecter une large gamme de systèmes par le moyen de logiciels de réseaux divers. Il est donc portable et indépendant du réseau auquel il est raccordé. Le FTS gère plusieurs utilisateurs, et plusieurs transferts simultanés. Il gère lui-même ses tâches à l'aide de son propre noyau. L'une des applications essentielles du FTS est le transfert de données à haut débit (2Mbits/s) par le satellite TELECOM 1 via le réseau HELIOS. Enfin, un exemple d'implantation du FTS est illustré dans le cas du système VM/CMS d'IBM et du logiciel de réseau NETEX de NSC.

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Silva, Flavio Morais de Assis. "Um refinamento da estrutura da camada de aplicação do RM-OSI/ISO e aspectos de sua implementação em um sistema didatico de comunicação." [s.n.], 1993. http://repositorio.unicamp.br/jspui/handle/REPOSIP/275961.

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Orientador : Edmundo Roberto Mauro Madeira Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Ciencia da Computação Made available in DSpace on 2018-07-18T10:06:41Z (GMT). No. of bitstreams: 1 Silva_FlavioMoraisdeAssis_M.pdf: 5100707 bytes, checksum: ed89630d5b32e158cf8326ca6ef2fcd6 (MD5) Previous issue date: 1993 Resumo: Esta dissertação consiste de Uma definição mais precisa de funcionalidades para os componentes da camada de Aplicação do RM-OSI/ISO (Reference Model - Open Systems Interconection / International Organization for Standardization). Esta definição de funcionalidades tem a finalidade de esclarecer os relacionamentos que há entre os componentes desta camada e de servir de uma base conceitual, a partir da qual estruturas para implementações possam ser derivadas. As funcionalidades apresentadas constituem um refinamento da estrutura definida pela ISO para esta camada. Também é apresentada a estrutura geral de implementação dos protocolos para um sistema didático de comunicação, chamado SISDI-0SI (Sistema didático para o Modelo OSI), que segue as padronizações do RM-OSI/ISO. Para este sistema descreve-se, em particular, como as estruturas de dados geradas por um compilador para alinguagem ASN.l são usadas na implementação destes protocolos. A dissertação consiste ainda da descrição de uma implementação do protocolo CCH (Commitment, Concurrency and Recovery), da camada de Aplicação do RM-0SI/ISO. Esta implementação foi feita utilizando-se a linguagem ESTELLE, que é uma Técnica de Descrição Formal definida pela ISSO, e faz parte do SISDI-OSI. A estrutura desta implementação foi feita de acordo com a definição de funcionalidades proposta Abstract: This thesis consists of a more accurate definition of functionalities for the components of the Application Layer of the RM-OSI/ISO (Reference Model - Open Systems Interconnection / International Organization for Standardization). This definition of functionalities intends to clarify the relationships that exist among the components of this layer and to serve as a basis of concepts, from which structures for implementations could be derived. The presented functionalities are a refinement of the structure defined by ISO for this layer. It also presents the general structure for the implementation of the protocols of a didactic communication system, called SISDI-OSI (Didactic System for OSI Model), which conforms to the standards from RM-OSI/ISO. For this system it is described, particularly, how the data structures generated by a compiler for the ASN language are used in the implementation of these protocols. This thesis also describes an implementation of the CCR (Commitment, Concurrency and Recovery) protocol, from the Application Layer of RM-OSI/ISO. This implementation was done using the language ESTELLE, that is a Formal Description Technique defined by ISO, and takes part in SISDI-OSI. The structure of this implementation was done according to the proposed functionalities Mestrado Mestre em Ciência da Computação

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Louge, Robert. "Un système de gestion réseau hétérogène en milieu industriel." Toulouse 3, 1992. http://www.theses.fr/1992TOU30158.

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La garantie du bon fonctionnement du systeme d'information, devenu point nevralgique de l'entreprise, est un probleme de plus en plus complexe. Les solutions apportees par les organismes de normalisation (osi), les consortiums ou directement les constructeurs se revelent partielles. Ainsi face a l'heterogeneite d'une part, et a l'evolutivite du reseau et des ses composants, seule une demarche progressive batie sur une architecture operationnelle d'un systeme de gestion reseau permet d'assurer un niveau de service optimum du systeme d'information. Un modele a trois niveaux (un gestionnaire de systemes homogenes, un superviseur, un hyperviseur) s'avere le plus apte a integrer l'existant, tout en evoluant au meme rythme que le reseau vers une structure plus coherente. L'architecture de chacun des niveaux est detaillee de maniere a fournir une base operationnelle a la realisation des fonctionnalites principales du systeme de gestion de reseau. Les travaux menes dans cette these proposent une demarche globale de mise en uvre du systeme de gestion en milieu operationnel. En effet, en s'appuyant sur les travaux de normalisation (aujourd'hui incomplet) nous demontrons la realite d'un systeme de gestion global disposant des fonctionnalites minimales et critiques, architecture de maniere a accueillir l'ensemble des domaines de gestion de reseaux, et suffisamment evolutif pour faire face au developpement permanent du reseau, de ses composants et des protocoles qu'il utilise

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Gurioli, Laura. "Protocollo di autenticazione STS e IKE." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14127/.

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Lo scambio delle chiavi di Diffie-Hellman fu il primo sistema a permettere a due interlocutori di condividere una chiave segreta senza l'utilizzo di un canale sicuro. La debolezza più grande di questo sistema è rappresentata dall'attacco "Man in the middle", in cui l'avversario riesce a porsi in mezzo alla comunicazione e impersonare i due interlocutori. Il protocollo STS (Station To Station) nasce nel 1987 per garantire maggiore sicurezza al protocollo base di Diffie-Hellman. Esso, grazie all'utilizzo della firma digitale, aggiunge l'autenticazione dei soggetti coinvolti nello scambio, impedendo così l'attacco Man in the middle. Rimangono, però, ancora possibili attacchi come quello di Lowe. Il protocollo STS, inoltre, è una delle basi per il protocollo di autenticazione standard per la sicurezza Internet, chiamato "Internet Key Exchange (IKE)". A questo proposito introduciamo lo standard ISO/OSI, composto da 7 livelli, e il protocollo IP che lavora al livello 3. Quest'ultimo si occupa dell'indirizzamento e instradamento dei dati che viaggiano in rete. IP è stato migliorato in IPSec per essere più resistente agli attacchi. L'autenticazione delle parti in IPSec è dovuta al protocollo IKE (Internet Key Exchange). Esistono diverse varianti di questo protocollo, in questa tesi vedremo soltanto le modalità basate sulla firma digitale.

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Marcin, Michal. "Aplikace objasňující základy fungování komunikačních protokolů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-413094.

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The diploma thesis aimed at the study of the topic of communication protocols and several transmission modes, as well as ARQ (Automatic Repeat Request) mechanisms. Subsequently, the task was to design and describe individual scenarios for their simulation. As a part of solving the mentioned task, it was necessary to create an application that allows the emulation of the behaviour of communication protocols without the need for a transmission in the real network a nd the requirements for the edition of the source code. The application was created in the Microsoft Visual Studio 2017 development environment using the C# programming language and .NET framework and it consists of a library and a graphical interface. The output of the solution is the application of a mode simulator of the data transmission in the network with two scenarios with the prepared input situations in the frame of graphical environment together with instructions, additional tasks and sample solutions. The program allows the simulation of the behaviour of communication protocols between the client and the server without the need for a transmission in a real network. In conclusion, the simulator of data transfer was created in the form of the desktop application which contains two scenarios. The first scenario is used to simulate ARQ mechanisms and the second one is active in the simulation of commutation of messages, circuits, packets or cells.

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Assoul, Saliha. "GELB (Gestion d'un Environnement de Communication Large Bande) : contribution à la conception d'un modèle de gestion pour le sous-réseau ATM." Toulouse 3, 1994. http://www.theses.fr/1994TOU30126.

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Suite a l'explosion du marche de l'interconnexion des reseaux locaux (lans) et aux offres de nouveaux services multimedia (la voix, les donnees et l'image), les reseaux a large bande (haut debit) prennent de plus en plus d'importance sur le marche des reseaux de telecommunications. Gerer un tel environnement est une tache tres importante et tres complexe, a cause des architectures heterogenes, des grandes vitesses de transmission, des larges couvertures et du deploiement de nouvelles techniques de transmission et de commutation (sdh et atm). Les approches de gestion utilisees dans les reseaux existants sont tres limitees pour garantir les performances attendues de ces reseaux. La gestion tmn du ccitt est celle de l'iso/nm-forum ne sont pas aujourd'hui suffisamment elaborees pour fournir a elles seules la solution recherchee. Cette these porte sur l'etude des nouveaux besoins en gestion dans l'environnement communication large bande. Elle analyse les problemes ainsi que les outils de gestion introduits par les nouvelles techniques deployees dans le but de proposer une methode de conception d'un systeme de gestion flexible et evolutif, basee sur la maitrise et la modelisation de l'environnement a gerer. Apres une ebauche de l'etat de l'art actuel dans le domaine de la gestion de reseaux heterogenes, cette these repose sur le principe de l'architecture d'administration pour les reseaux metropolitains, developpee au sein de notre laboratoire dans le cadre du projet esprit: max (metropolitan area communication system). Nous definissons le modele integrateur gelb pour l'environnement de communication large bande. Une specification detaillee du gestionnaire du sous-reseau atm est ensuite decrite. Enfin, sont presentees les demarches d'implantation de ce module pour une application d'interconnexion de reseaux locaux

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Bassi, Lorenzo. "Orchestration of a MEC-based multi-protocol IoT environment." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/24114/.

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Nowadays we are witnessing to a continuous increasing of the number of IoT devices that must be configured and supported by modern networks. Considering an industrial environment, there is a huge number of these devices that need to coexist at the same time. Each one of them is using its own communication/transport protocol, and a huge effort needs to be done during the setup of the system. In addition, there are also different kind of architectures that can be used. That’s why the network setup is not so easy in this kind of heterogeneous environment. The answer to all these problems can be found in the emerging cloud and edge computing architectures, allowing new opportunities and challenges. They are capable of enable on-demand deployment of all the IoT services. In this thesis is proposed a Multi-access Edge Computing (MEC) approach to face all the possible multi-protocol scenarios. All the services are transformed into MEC-based services, even if they are running over multiple technological domains. As result, was proved that this kind of solution is effective and can simplify the deployment of IoT services by using some APIs defined by the MEC standard. As above mentioned, one of the most important tasks of these new generation’s networks is to be self-configurable in very low amount of time and this will be the scope of my research. The aim of this thesis is to try to reduce as much as possible the time that a certain network requires to be self-configured in an automatic way considering an Industrial IoT as a Service (IIoTaaS) scenario.

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Scarlato, Michele. "Sicurezza di rete, analisi del traffico e monitoraggio." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/3223/.

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Il lavoro è stato suddiviso in tre macro-aree. Una prima riguardante un'analisi teorica di come funzionano le intrusioni, di quali software vengono utilizzati per compierle, e di come proteggersi (usando i dispositivi che in termine generico si possono riconoscere come i firewall). Una seconda macro-area che analizza un'intrusione avvenuta dall'esterno verso dei server sensibili di una rete LAN. Questa analisi viene condotta sui file catturati dalle due interfacce di rete configurate in modalità promiscua su una sonda presente nella LAN. Le interfacce sono due per potersi interfacciare a due segmenti di LAN aventi due maschere di sotto-rete differenti. L'attacco viene analizzato mediante vari software. Si può infatti definire una terza parte del lavoro, la parte dove vengono analizzati i file catturati dalle due interfacce con i software che prima si occupano di analizzare i dati di contenuto completo, come Wireshark, poi dei software che si occupano di analizzare i dati di sessione che sono stati trattati con Argus, e infine i dati di tipo statistico che sono stati trattati con Ntop. Il penultimo capitolo, quello prima delle conclusioni, invece tratta l'installazione di Nagios, e la sua configurazione per il monitoraggio attraverso plugin dello spazio di disco rimanente su una macchina agent remota, e sui servizi MySql e DNS. Ovviamente Nagios può essere configurato per monitorare ogni tipo di servizio offerto sulla rete.

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Zwecker, Stella. "Représentation et spécification d'architectures d'interconnexion de réseaux hétérogènes vers la définition d'une base de connaissances." Toulouse 3, 1993. http://www.theses.fr/1993TOU30052.

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L'objet de cette these est de definir une methodologie pour la specification d'architectures d'interconnexion de reseaux heterogenes, et d'integrer cette methodologie au sein d'un systeme base sur l'utilisation de techniques d'intelligence artificielle. La methodologie permet: 1) d'evaluer l'incompatibilite des reseaux a interconnecter (lorsque des adressages et/ou les couples service-protocole d'une couche sont incompatibles, les entites de cette couche sont incapables de s'identifier et/ou de dialoguer), 2) de realiser une specification orientee fiabilite de l'architecture d'interconnexion resultante (les deux techniques proposees, la conversion et l'encapsulation, permettent de controler les incompatibilites des reseaux a partir d'une certaine couche de leur architecture). Pour integrer la methodologie au sein d'un systeme a base de connaissances, les differents concepts mis en jeu ont ete representes (en particulier une modelisation generale des adressages au sein d'une architecture multi-couches a ete definie). Le prototype implante combine deux formalismes de representation des connaissances (formalisme oriente objets; langage prolog). Ce systeme met en oeuvre des sessions interactives, qui fournissent a un utilisateur des guides pedagogiques pour l'etude de cas d'interconnexion de reseaux: par exemple reseaux longue distance de type x25 ou ip (i. E. Dont la couche reseau est avec ou sans connexion); reseaux locaux de type ieee 802 sans couche reseau, etc.

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Sene, Júnior Iwens Gervásio. "Comparação de modelos de agentes para gerenciamento de redes :: uma abordagem via simulação /." Florianópolis, SC, 1997. http://repositorio.ufsc.br/xmlui/handle/123456789/77041.

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Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Made available in DSpace on 2012-10-17T00:16:01Z (GMT). No. of bitstreams: 0Bitstream added on 2016-01-08T22:40:49Z : No. of bitstreams: 1 143134.pdf: 2109990 bytes, checksum: 4599c248309f00a4e25b5db2dc82161e (MD5)

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Benkhellat, Mohand Lyazid. "Formalisation et vérification de l'interopérabilité dans les systèmes de communication." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL001N.

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Cette thèse traite de la validation de la propriété d'interopérabilité entre un ensemble d'équipements dans les systèmes et applications distribués temps réel. Contrairement au peu de travaux qui ont été déjà menés sur le sujet et qui proposent une validation basée sur la technique de test sur plate-forme, nous avons proposé une méthodologie de validation basée sur une technique de vérification. Etant donné un système composé d'un ensemble d'équipements avec leurs caractéristiques de conformité et un ensemble de processus d'application distribués, la validation de la propriété d'interopérabilité du système par notre approche revient à construire dans un formalisme mathématique le modèle du système et à définir la relation d'interopérabilité en fonction des propriétés régissant la communication puis de vérifier la correction de la relation dans le modèle. L'étude de la problématique a permis de décomposer l'interopérabilité des systèmes de communication selon le modèle OSI et d'identifier quatre classes de caractéristiques des équipements et donc quatre types d'interopérabilité : en services, en protocoles, en ressources et en performances temporelles. L'approche a été concrètement mise en œuvre pour la vérification de l'interopérabilité de services et temporelle à propos d'un système de communication selon le modèle producteur/distributeur/consommateurs. Le système est modélisé et la relation est décrite par des techniques formelles adaptées aux deux types d'interopérabilité

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Araujo, Olga Fernanda Nabuco de. "Proposta para utilização de rede de comunicação em uma celula-nivel de aquisição e atuação." [s.n.], 1997. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263214.

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Orientador: João Mauricio Rosario Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica Made available in DSpace on 2018-07-22T10:22:49Z (GMT). No. of bitstreams: 1 Araujo_OlgaFernandaNabucode_M.pdf: 7882644 bytes, checksum: 7f2b7fbc61b4a64e0be4e54748ec5d70 (MD5) Previous issue date: 1997 Resumo: Neste trabalho procura-se demonstrar a adequabilidade do uso de sistemas de comunicação tipo Fieldbus na Célula de manufatura da Plataforma Industrial de Pesquisa, Experimentação e Formação em Automação, PIPEFA, que é um projeto conjunto entre CTI e Unicamp. Para isto foram descritos os vários sistemas que compõem a Plataforma segundo a ótica do modelo de referência NBS, de modo a se obter uma visão geral do problema. Com foco no sistema de comunicação, foi feita uma explanação das restrições que um sistema deste tipo deve possuir. Dentro deste enfoque, são mostrados três sistemas de comunicação que satisfazem estes requisitos: FIP, Profibus e IEC 1158 (SP-50). É feita então uma proposta do uso de equipamentos que utilizam Profibus, em um dos centros de montagem/desmontagem da PIPEFA Abstract: This work aims demonstrate the feasibility of using communication systems like Fieldbus in a manufacturing cell. This cell is part of PIPEFA - Industrial Platform for Research, Teaching and Tranining in Automation - project, a joint effort involving CTI and Unicamp. PIPEFA's functionality is described using NBS as reference model. The focus is on the shop floor communication system, in this sense a generic explanation of the restrictions applied to real time systems is exposed. A survey of Fieldbus systems, FIP, IEC 1158 (SP-50) and Profibus, which follow real time system requirements is also presented. Finally the use of Profibus equipment in the PIPEFA's assembly work center is proposed. Mestrado Mecanica dos Sólidos e Projeto Mecanico Mestre em Engenharia Mecânica

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Chassot, Christophe. "Architecture de transport multimédia à connexions d'ordre partiel." Toulouse, INPT, 1995. https://tel.archives-ouvertes.fr/tel-00145820.

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Les travaux presentes dans ce memoire ont pour cadre la recherche de nouveaux services et protocoles de transport, aptes a supporter le transfert de donnees multimedia en tenant compte des exigences applicatives en termes de hauts debits et de synchronisation. L'approche proposee repose sur la definition et le developpement d'un nouveau concept: la connexion d'ordre partiel (poc - partial order connection), etablissant un lien conceptuel entre les modes de service/protocole orientes-connexion tels que tcp, et sans connexion tels que udp. Une poc est une connexion de bout en bout permettant de definir et de mettre en uvre tous les services et protocoles d'ordre partiel entre deux entites communicantes ; dans une poc, la delivrance des donnees a l'utilisateur recepteur peut etre effectuee dans un ordre different de l'ordre de soumission de ces donnees par l'utilisateur emetteur: la difference (acceptable) entre ces deux ordres resulte de la definition, par l'utilisateur, d'un ordre partiel de delivrance lors de l'ouverture de la connexion. Une formalisation des mecanismes correspondants est proposee au moyen de la technique de description formelle estelle. Les caracteristiques intrinseques des differents media d'un flux multimedia ont conduit ces dernieres annees au developpement d'architectures de communication integrant la prise en compte des contraintes applicatives a differents niveaux conceptuels, et notamment au niveau transport du modele osi ; a partir d'une modelisation de ces contraintes utilisant le formalisme des reseaux de petri (le modele tspn), l'auteur propose d'integrer le concept de poc dans une architecture de transport multimedia autorisant une prise en compte globale des contraintes d'ordre et de fiabilite d'un flux multimedia. Les mecanismes de gestion de l'ordre et de la fiabilite qui sont proposes permettent de definir un service de transport multimedia offrant une hypothese nouvelle aux utilisateurs vis a vis de la problematique de la synchronisation. Une etude de la faisabilite d'un protocole multimedia d'ordre partiel a l'aide des procedures xtp est finalement presentee: elle conclut en la possibilite d'une telle realisation

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Lutmann, Patrice. "Transfert et visualisation d'images numériques." Bordeaux 1, 1996. http://www.theses.fr/1996BOR10715.

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L'image est aujourd'hui un support privilegie de la communication. De plus en plus d'applications informatiques font appel aux images ou sont dediees a la manipulation d'images. Pour ces applications, les principaux besoins sont le stockage, le transfert et la visualisation. A partir de l'analyse de ces besoins, specifiquement le transfert et la visualisation, je definis les principales caracteristiques du transfert et de la visualisation des images. Les difficultes et contraintes essentielles que l'on rencontre alors sont l'heterogeneite des materiels et des logiciels utilises, les debits et les delais. Je propose ensuite divers modeles d'implementation et en particulier une integration des services de transfert et de visualisation dans l'environnement graphique x, sous systeme d'exploitation unix avec tcp/ip. Les services de transfert et de visualisation d'images, designes par stvi pour les services et sirix pour le prototype implemente, vont etre integres au systeme graphique x pour la partie visualisation, et a tcp/ip pour le transport. Ces deux services appartiennent a la couche application et presentation du modele de reference osi. Ils sont en etroite relation avec le service d'image de la bddri et le service de visualisation du systeme x. En fonction des besoins de l'application, ces services permettent de determiner les parametres de profil optimum pour minimiser le volume des donnees a transferer. Ils presentent une interface generique de visualisation, exploitent les ressources de chacun des acteurs en fonction des capacites relatives de ceux-ci. Enfin, ils gerent les contraintes temporelles necessaires a la visualisation acceptable de sequences animees. Je presente les diverses associations permettant le controle du transfert, la commande du transfert et la visualisation. J'analyse les flux de donnees et la localisation des traitements ainsi que leur influence sur la realisation de ces associations et les contraintes d'implementation. Je decris aussi le systeme x et l'impact de ce systeme sur sirix. J'etudie les diverses possibilites d'implementation de ces services et leur integration au systeme x, et je compare les divers modeles realises tant du point de vue des fonctionnalites que des performances

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Cerqueira, Eduardo Coelho. "Implementação de um software discriminador de repasse de eventos para a arquitetura internet." Florianópolis, SC, 2003. http://repositorio.ufsc.br/xmlui/handle/123456789/85901.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação. Made available in DSpace on 2012-10-21T01:04:59Z (GMT). No. of bitstreams: 1 205995.pdf: 1081924 bytes, checksum: 75cba0eb22c6f6e50d5ac0a2a938ae1c (MD5) Este trabalho apresenta um Software Discriminador deRepasse de Eventos (SDRE) construído em Java, aplicando as funcionalidades do modelo OSI em ambientes SNMP. É feita uma revisão bibliográfica das duas arquiteturas de gerência de redes, buscando adequar a norma OSI/ITU-T X-734 à Internet e são apresentadas motivações que demonstram esforços atuais nesta área. Esta aplicação é simples e funcional, enfatizando a técnica de relatório de eventos, filtrando os mesmos e podendo selecionar várias estações de gerenciamento destinatárias, como forma de descentralizar e melhorar o desempenho da arquitetura de gerência de redes Internet. Por fim são apresentados os resultados dos testes efetuados, a avaliação e a validação do software, bem como o ambiente simulado e de produção onde foi implantado o discriminador.

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