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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
921

Metoda za povezivanje mernog sistema i računarapomoću konverzije podataka iz I2S u TCP/IP protokol / Method for Connecting Measuring System With Computer by Converting Data From I2S to TCP/IP Protocol

Sakal Tibor 01 June 2017 (has links)
<p>Ova doktorska disertacija predstavlja istraživački rad sproveden sa ciljem da re&scaron;i problem koji se odnosi na realizaciju povezivanja laboratorijskog, medicinskog mernog uređaja sa personalnim računarom. Rezultat istraživačkog rada je op&scaron;ta metoda koja obezbeđuje efikasnu konverziju podataka I2S protokola u TCP/IP protokol.</p> / <p>This doctoral thesis presents the research work carried out in order to solve a practical problem, the realization of a connection between a medical measuring device and a personal computer. The result of the research is a general method that provides efficient data conversion from the I2S protocol to the TCP/IP protocol.</p>
922

An Internet content overview and implementation on an IP based set-top box

Widborg, Linus January 2006 (has links)
<p>This thesis covers the investigation of different content sources on the Internet and the analysis of the requirements they put on a set-top box. It also covers the adaptation of the set-top box to one of these sources. </p><p>An IP based set-top box (IP-STB) is mainly constructed for access to TV and video distributed over a high speed network. The IP-STB is also connected to the Internet and it potentially has access to all of the Internet based content. This could provide the user of the IP-STB with a lot of new services and was the stating point for my thesis work.</p><p>The goal of this thesis was to make a broad investigation of different content sources on the Internet and to adapt an IP-STB to one of them. </p><p>The investigation focused on streaming media content and how it was distributed over the Internet. It resulted in a representative overview of the streaming media content available and how the content is distributed. The IP-STB was adapted to handle the Streaming HTTP protocol which made it possible to listen to web radio transmissions from Sveriges Radio and other providers using the same protocol for their distribution.</p>
923

Le support de VoIP dans les réseaux maillés sans fil WiMAX en utilisant une approche de contrôle et d'assistance au niveau MAC

Haddouche, Fayçal 04 1900 (has links)
Les réseaux maillés sans fil (RMSF), grâce à leurs caractéristiques avantageuses, sont considérés comme une solution efficace pour le support des services de voix, vidéo et de données dans les réseaux de prochaine génération. Le standard IEEE 802.16-d a spécifié pour les RMSF, à travers son mode maillé, deux mécanismes de planifications de transmission de données; à savoir la planification centralisée et la planification distribuée. Dans ce travail, on a évalué le support de la qualité de service (QdS) du standard en se focalisant sur la planification distribuée. Les problèmes du système dans le support du trafic de voix ont été identifiés. Pour résoudre ces problèmes, on a proposé un protocole pour le support de VoIP (AVSP) en tant qu’extension au standard original pour permettre le support de QdS au VoIP. Nos résultats préliminaires de simulation montrent qu’AVSP offre une bonne amélioration au support de VoIP. / Wireless mesh networks (WMNs), because of their advantageous characteristics, are considered as an effective solution to support voice services, video and data in next generation networks. The IEEE 802.16-d specified for WMNs, through its mesh mode, two mechanisms of scheduling data transmissions; namely centralized scheduling and distributed scheduling. In this work, we evaluated the support of the quality of service (QoS) of the standard by focusing on distributed scheduling. System problems in the support of voice traffic have been identified. To solve these problems, we proposed a protocol for supporting VoIP, called Assisted VoIP Scheduling Protocol (AVSP), as an extension to the original standard to support high QoS to VoIP. Our preliminary simulation results show that AVSP provides a good improvement to support VoIP.
924

Lastfördelning och effektmätning med Arduino och PLC

Klintrot, Oskar, Forsström, Daniel January 2014 (has links)
Detta arbete var beställt av Sjöfartshögskolan i Kalmar. Skolan ville ha en enhet som kunde mäta aktiv-, reaktiv- och skenbar effekt, ström, spänning, frekvens och cosϕ på en generator och som kommunicerade vidare dessa värden till en PLC. Detta för att kunna lastfördela lasten mellan ett antal generatorer i kursen Tillämpad elteknik 15 hp där studenterna bygger en generatorinstallation med tre generatorer. Ett funktionsblock för lastfördelning skulle också programmeras. Prototypen som konstruerades baserades på en Arduino Ethernet och kommunikationen löstes med Modbus TCP/IP över Ethernet. Ett lastfördelningsprogram programmerades i form av ett funktionsblock som studenterna kunde importera till CoDeSys v2.3 och använda i sina installationer. Prototypen kunde läsa av värdena med ungefär samma noggrannhet som ett kommersiellt instrument som använder sig av samma mätteknik som prototypen. Uppdateringsfrekvensen var dock lägre än hos ett kommersiellt instrument. Kommunikationen med PLC:n fungerade utan problem. Då ingen undervisning hölls i arbetets slutskede kunde inte lastfördelningen testas på en fullskalig anläggning. Lastfördelningsprogrammet klarade dock av att hålla rätt frekvens på en ensam generator och fungerade som tänkt när programmet testades i en simulator. Prototypen gav fel mätvärden vid kapacitiv last. Vid jämförelse med en kommersiell tångamperemeter visade sig mätfelet bero på mätmetoden då båda gav liknande resultat. Som referens användes en professionell elkvalitetsanalysator. Alla uppdragsgivarens krav blev uppfyllda och arbetet kommer att kunna användas i undervisningen. / This thesis was ordered by Kalmar Maritime Academy. The request was for a device that could measure active, reactive and apparent power, as well as frequency, voltage, current and cosϕ on a generator. The measured values would be communicated to a PLC for use in a load sharing program between a number of generators in the course Tillämpad elteknik, 15 ECTS. In that course the students constructs a three-generator electric power grid. Included in the request was also to program a load sharing program. The prototype being constructed was based on the Arduino Ethernet, and the communication was enabled by means of the Modbus TCP/IP protocol over Ethernet. A load sharing program was created in the form of a function block which the student could import into the CoDeSys for use in the generator systems. The prototype could measure values with close to the same accuracy as a commercial available instrument that were using the same technique for measuring. The refresh rate was however lower than the commercial available instrument. Communication with the PLC worked without any issues. No full-scale testing could be done since no course was held during the final stages of the thesis, however the load sharing program could keep frequency on a single generator alone and worked in a simulated soft environment. Measuring errors occurred when measuring a capacitive load. When comparing to a commercial available clamp meter, the same errors occurred. As a reference a professional power and energy quality analyser was used. All the requests were fulfilled and the result of this thesis will be used in the educational programme at the Academy.
925

Essays on competitive analysis : firm strategies and market structure /

Jahn, Eric. January 2007 (has links) (PDF)
University, Diss.--Frankfurt (Main), 2007.
926

Managing IP networks with Cisco routers /

Ballew, Scott M. January 1900 (has links)
Includes index.
927

Customer-based IP service monitoring with mobile software agents /

Günter, Manuel, January 2002 (has links)
Univ., Diss. u.d.T.: Günter, Manuel: Management of multi provider Internet services with software agents--Bern, 2001.
928

[en] GENERATION OF BUILT-IN OPTICAL INTELIGENCE ON ETHERNET / IP NETWORKS / [pt] GERAÇÃO DE INTELIGÊNCIA ÓPTICA EM REDES ETHERNET / IP

HENRIQUE JOSE PINTO PORTELA DA SILVA 06 July 2005 (has links)
[pt] O principal objetivo desta dissertação consiste na geração de novas funcionalidades inteligentes em redes ópticas associadas aos protocolos IP e Gigabit Ethernet, através da utilização de circuitos integrados programáveis operando na taxa do Gigabit. A padronização Ethernet é apresentada através das camadas PHY e MAC, destacando suas funções, interfaces e os tipos de chips disponíveis no mercado. A camada PHY do padrão Ethernet para meios ópticos é detalhada. Algumas tecnologias de chips são discutidas, entre elas o crescimento dedicado, os ASICs, as NPUs e as tecnologias programáveis: FPGAs e CPLDs. O conceito de inteligência óptica e o perfil de camadas equivalentes associados a este conceito são introduzidos. Um novo elemento de rede dedicado à inserção de sinalização na camada óptica é apresentado, destacando-se sua estrutura, sua realização, seu detalhamento para utilização em redes. Diversas montagens experimentais com o elemento desenvolvido são utilizadas para demonstrar as características do sistema, entre elas a eficiência da utilização da tecnologia de FPGAs e a transparência da inteligência na camada óptica para o padrão Ethernet. / [en] The main objective of this work is the generation of new functionalities in optical networks, associated to the Ethernet and IP protocols, by the use of programmable integrated circuits operating in Gigabit rates. The Ethernet standard is presented through its PHY and MAC layers, highlighting its functions, interfaces and the types of commercially available ICs. The Ethernet standard PHY layer for optical media is described. Some IC technologies are discussed, such as dedicated growth, ASICs, NPUs and the programmable technologies: FPGAs e CPLDs. The concept of built-in optical intelligence and a new layers model associated to it are presented. A new network element, dedicated to the insertion of signaling in the optical layer is also presented, and special attention is dedicated to its structure, to its implementation and to the aspects of its use in networks. Several experimental setups using the developed element are shown, demonstrating the characteristics of the system, particularly the efficiency obtained by the use of FPGA technology and the transparency of the optical intelligence with respect to the Ethernet standard.
929

OrchFlow: uma arquitetura para orquestração de redes OpenFlow com múltiplos controladores / OrchFlow: an architecture for orchestration of OpenFlow networks with multiple controllers

Frate, Marcelo 23 February 2017 (has links)
Submitted by Milena Rubi (milenarubi@ufscar.br) on 2017-10-09T14:35:22Z No. of bitstreams: 1 FRATE_Marcelo-2017.pdf: 8466810 bytes, checksum: 9438c26c84ebe90cd741672c8c04d726 (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-10-09T14:35:33Z (GMT) No. of bitstreams: 1 FRATE_Marcelo-2017.pdf: 8466810 bytes, checksum: 9438c26c84ebe90cd741672c8c04d726 (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-10-09T14:35:45Z (GMT) No. of bitstreams: 1 FRATE_Marcelo-2017.pdf: 8466810 bytes, checksum: 9438c26c84ebe90cd741672c8c04d726 (MD5) / Made available in DSpace on 2017-10-09T14:35:53Z (GMT). No. of bitstreams: 1 FRATE_Marcelo-2017.pdf: 8466810 bytes, checksum: 9438c26c84ebe90cd741672c8c04d726 (MD5) Previous issue date: 2017-02-23 / Não recebi financiamento / Since the emergence of the Software-Defined Networking (SDN), and, more precisely, since the development of an open interface in 2008 called OpenFlow protocol, it is being observed that this new networking paradigm is deeply remodeling the IP-protocol- based networks. It means that new mechanisms of provision services are being possible, which ensures scalability and reduces costs. Although this new paradigm has been created to centralize the control logic, there is the possibility of decentralizing it through the parceling of control tasks between two or more controllers. In this scenario, the subdivision of administrative domain in smaller subdomains in order to have each of them being controlled by one single controller has been an alternative to ensure scalability in SDN. The OpenFlow protocol allows communication among switches and controllers to another controller. However, the protocol does not define how this communication between one controller to other should be done. It is mandatory, therefore, the development of protocol independent solutions able to distribute this logic inside the same administrative domain. New proposals have been arisen, but their applications either use equal controllers or demand the development of new controllers specifically designed. This master’s research aims to offer the fundamentals to the development of an architecture here so called Orch Flow, able to receive application demands and organize them in a way it provides requested services through an OpenFlow network designed with two or more different implementation controllers. The OrchFlow architecture that is being proposed accomplishes its task through handling multiple OpenFlow controllers hierarchically and providing network access through three distinct modes: Proactive, Reactive and Hybrid. / Desde o surgimento das Redes Definidas por Software e mais especificamente à partir de 2008 com o desenvolvimento de uma interface aberta, o protocolo OpenFlow, é possível observar que este novo paradigma de redes está revolucionando as redes baseadas no protocolo IP, possibilitando a criação de novos mecanismos de aprovisionamento de serviços, garantindo a escalabilidade e reduzindo custos. Embora este novo paradigma tenha sido criado para a centralização da lógica de controle, existe a possibilidade de descentralizá-la através da divisão das tarefas de controle entre dois ou mais controladores. Neste cenário, subdividir o domínio administrativo em subdomínios menores e fazer com que cada subdomínio seja controlado por um controlador tem sido uma alternativa para garantir escalabilidade em Software-Defined Networking (SDN). O protocolo OpenFlow permite a comunicação entre switches e controladores, entretanto ele não define como deve ser feita a comunicação de um controlador para outro controlador. Faz-se necessário, portanto, o desenvolvimento de soluções independentes do protocolo, capazes de distribuir essa lógica dentro de um mesmo domínio administrativo. Neste cenário, novas propostas vão surgindo, porém as aplicações desenvolvidas ou fazem uso de controladores iguais ou são criados novos controladores especificamente para essa finalidade. Esta pesquisa de mestrado tem como objetivo o desenvolvimento de uma arquitetura, aqui denominada de OrchFlow, capaz de receber solicitações de aplicações, orquestrando as requisições a fim de prover os serviços solicitados numa rede OpenFlow com dois ou mais controladores de implementações diferentes. A arquitetura OrchFlow, desenvolvida para esta pesquisa de mestrado, realiza essa tarefa através da orquestração de múltiplos controladores OpenFlow atuando de forma hierárquica, provendo o acesso à infraestrutura da rede através de três modos distintos: o Proativo, o Reativo e o Híbrido.
930

Uma arquitetura de nomeação para a internet utilizando redes virtuais

Sousa, Joelle Quaini 26 November 2007 (has links)
Made available in DSpace on 2016-06-02T19:05:31Z (GMT). No. of bitstreams: 1 2017.pdf: 2776743 bytes, checksum: cc39daf3470ef4356480296d650d108c (MD5) Previous issue date: 2007-11-26 / Regarding new computational and networking requisites such as wireless networks, mutihoming interfaces, load-balancing mechanisms and several other middleboxes [1] present today, these facts, allied to the static and conservative nature of the Internet and its sheer size turn the capability to correct these problems an almost impossible attempt, as it demands structural changes. In the Internet inception, in the late 70th, neither mobility nor multihoming where foreseen in its original intents. In this sense, the proposition of a novel naming architecture for the Internet to identify univocally services and data, irrespective to its node characteristics, would have an acute changing effect and will allow its elements to be precisely represented and authenticated. In order to achieve these purposes, the use of Virtual Networks was considered as it allows the incremental introduction of new technologies, protocols and applications being itself a more viable alternative when compared to several failed attempts to introduce new structural changes to the Internet [2; 3]. A proposal for a taxonomy for Virtual Networks was described here as a result of a site survey that was conducted to function as subject to this architecture proposition. Besides, a literature investigation of related projects followed by a network testbed of several protocols originated the proposition of a Layered Naming Architecture for the Internet using Virtual Networks. / Face a vários novos requisitos de comunicação demandados por equipamentos em desenvolvimento constante, tais como computadores móveis portadores de múltiplas interfaces comunicantes, devido à inserção de diversos middleboxes [1], o modelo arquitetural TCP/IP necessita ser aprimorado para suportar novas tecnologias e protocolos. Originalmente, quando a Internet foi projetada, no final dos anos 70 nem mobilidade nem multihoming (i.e. equipamento com diversas conectividades físicas simultâneas) foram considerados. Pela proposição de uma nova arquitetura de nomeação para a Internet, que seja capaz de identificar univocamente qualquer entidade comunicante, bem como proporcionar suporte às tecnologias já extensamente utilizadas, este trabalho objetivou promover a mobilidade e o suporte a diversos middleboxes para a Internet, principalmente no que diz respeito à identificação e à autenticação de nós e objetos (i.e. serviços, dados e usuários). Almejando atingir tal objetivo utilizou-se a tecnologia de Redes Virtuais, que permite uma adesão incremental de suas funcionalidades, protocolos e aplicações. Esta abordagem não representa, portanto, um modelo cujas mudanças à arquitetura da Internet causam-lhe transformações estruturais, diferentemente de outras propostas que abordaram este problema desta forma sem sucesso [2; 3]. Para tanto, uma taxonomia de Redes Virtuais foi proposta e avaliada por um estudo de caso que compreendeu a sua aplicação prática. Além disso, realizou-se uma análise de bancada de redes de diversos protocolos e o estudo das propostas da literatura associada. Tais realizações culminaram na proposta de uma Arquitetura de Nomeação para a Internet utilizando Redes Virtuais Overlay.

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