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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.
31

Self-Configuration and Monitoring of Service Specific Overlay Networks

Abdeljaouad, Imad 18 March 2013 (has links)
The constant growth in network communications technologies and the emergence of Service Specific Overlay Networks (SSONs), coupled with the rapid development of multimedia applications make the management of such technologies a major challenge. This thesis investigates the SSONs management problem and proposes an autonomic architecture, a self-organizing and self-adapting algorithm, and a utility function for monitoring the Quality of Experience (QoE) of IPTV streams in SSONs. First, we examine the different issues stemming from the autonomic management of SSONs and identify the limitations of existing approaches. We then propose an architecture to ease the management of SSONs by incorporating autonomic computing principles to make SSONs acquire self-management capabilities. The proposed architecture introduces autonomic control loops that continuously monitor network components and analyze the gathered data. An Autonomic System (AS) is comprised of one or more Autonomic Managers (AM) which take control of managing other elements in the network. The proposed architecture highlights the different components of an AM and identifies its purpose. The distributed nature of the proposed architecture avoids limitations of centralized management solutions. We then propose a scheme to allow AMs to emerge among the set of nodes in the network as the most powerful ones in terms of different factors, including processing capabilities and stability. Using a self-organizing and self-adapting distributed protocol, each node in the overlay selects an appropriate AM to report to so that sensed data is delivered error-free, and in a timely manner, while the load is distributed over the AMs. Finally, we propose a utility function to monitor the quality of IPTV streams by predicting QoE based on statistical Quality of Service (QoS) information. The proposed function is simple and does not require high processing power. It allows the QoE of IPTV users to be monitored in real-time by the AMs, so that quality degradations are accurately identified and adaptation mechanisms are triggered at the right moment to correct issues causing degradations. Theoretical analysis and simulations studies are presented to demonstrate the performance of the proposed schemes.
32

Traffic modeling and performance analysis for IPTV systems

Wan, Fengdan 11 August 2008 (has links)
Internet protocol TV (IPTV) is predicted to be the key technology winner in the future. It has, however, stringent quality of service (QoS) requirements. When IPTV traffic shares the network resources with other traffic like data and voice, how to ensure their QoS and efficiently utilize the network resources is a key and challenging issue. In this thesis, Class based queueing (CBQ) is suggested to deploy at the bottleneck router to allow heterogeneous traffic share network resources fairly and efficiently. Then, we propose a two-level Markovian video traffic model and develop a fluid flow based analytical framework to quantify the performance of IPTV systems and derive the admission regions to ensure the QoS of IPTV traffic. The proposed two-level Markovian traffic model exploits both the temporal and spatial complexity of video traffic. The model can easily be incorporated to network simulators. The fidelity of the proposed video model and the effectiveness of the analytical framework are verified by network simulations driven by real video traces. Given the traffic model, a fluid flow based analytical framework is developed to study the queueing behaviors of IPTV traffic in wired, single-hop and multi-hop wireless networks. The analytical results provide insights in how traffic characteristics and network parameters affect the network performance. To ensure the QoS of heterogeneous traffic, admission regions of a wired or wireless bottleneck, with or without CBQ are obtained. The simulation and analytical results both illustrate that time-varying wireless link accommodates much less IPTV connections than the wired link with fixed data rate. The variations of both the incoming traffic arrival rate and the outgoing service rate affect the network performance and admission region. Therefore, it is recommended to deploy proper traffic shaping and resource management schemes in order to support IPTV traffic more efficiently.
33

Diseño de un Laboratorio de Televisión Digital con Fines Docentes

Carrillo Ramírez, Paula Cecilia January 2008 (has links)
La presente memoria tiene como objetivo el diseño de un laboratorio de IPTV (Internet Protocol Television) que contribuye a la docencia del Departamento de Ingeniería Eléctrica de la Universidad de Chile en la formación de ingenieros del área de las Telecomunicaciones. El diseño se centra en el estudio de la arquitectura, componentes y funcionamiento de una plataforma IPTV básica. La metodología se basa en realizar un análisis de las diferentes alternativas de equipos, software y hardware disponibles actualmente en el mercado considerando sus ventajas, desventajas y principales características. Sobre la base del análisis anterior se eligen las mejores alternativas para cada una de las etapas del sistema, se realiza una implementación de prueba que permita comprobar su funcionamiento en una red pequeña. Basado en esta experiencia se propone una topología, direccionamiento, dimensionamiento y método de instalación como formalización del diseño. Para la plataforma propuesta se elaboran prácticas experimentales para el desarrollo de un curso de IPTV con un enfoque teórico y aplicado para el apoyo a la docencia. Estas experiencias se centran en los aspectos característicos de esta tecnología y se acompañan de diferentes herramientas de análisis para el uso por parte de los alumnos. El diseño de esta plataforma IPTV se compara con una de un operador telefónico que actualmente ofrece además el servicio de Televisión Digital mediante banda ancha. De esta comparación se concluye que exceptuando las diferencias en costos de los equipos, la plataforma diseñada permite en forma didáctica conocer los aspectos básicos de esta tecnología.
34

Diseño e Implementación de una Plataforma IP/TV Tipo MYTHTV, Económica y con Fines Docentes

Robles Kukuljan, Cristian David January 2008 (has links)
En la actualidad, el creciente interés por las nuevas tecnologías relacionadas con la televisión ha dado pie a numerosos estudios, por un lado se encuentran las industrias que han mejorado la calidad de la imagen, por otro lado en todos los continentes se están implementando nuevos estándares de televisión. Estos avances vienen acompañados del crecimiento que ha mostrado Internet en los últimos años, primero por su versatilidad y segundo por su rapidez. Los avances que ha tenido Internet, tanto en sistemas operativos como en infraestructura, más el constante progreso de nuevas herramientas computacionales, ha ampliado la gama de servicios brindados por las telecomunicaciones, que es precisamente donde se establece el tema de esta memoria, la cual desarrolla una plataforma donde convergen estas mejoras. Considerando el gran interés del mercado por la televisión, se evalúa positivamente el diseño e implementación de una plataforma de servicios IP/TV enfocado en un grabador personal de video a través de una red IP local, con el mismo fundamento de MythTV y similar al sistema TiVo comercializado en USA, pero con la ventaja de no requerir costos operacionales por licencias de Softwares ni por costos de soporte de parte de las empresas. El trabajo realizado se llevó a cabo con herramientas computacionales Open Source, las que permiten su uso gratuitamente con soporte brindado por las comunidades que las desarrollan. Así, se efectuó la implementación de una plataforma de streaming de video a través del protocolo Internet con servicios como solicitar videos, transmitir televisión en directo y programar grabaciones de emisiones televisivas. Una aplicación de este tipo es una motivación para el cliente, dado que permite no perder programas que se transmitan en horarios inaccesibles. La metodología seguida consiste en implementar las distintas etapas que permiten alcanzar el diseño propuesto, esto a través de la selección, utilización y combinación de las herramientas que entreguen a la plataforma las características deseadas. Además, incluye una guía para recrearla de modo que pueda ser utilizada con fines docentes en laboratorios de pregrado. También se puede utilizar en futuros trabajos de memoria o tesis integrándose en otras soluciones de Streaming que la hagan converger con más servicios en una sola plataforma, estos contenidos y proyecciones otorgan a esta memoria un considerable valor docente.
35

Self-Configuration and Monitoring of Service Specific Overlay Networks

Abdeljaouad, Imad January 2013 (has links)
The constant growth in network communications technologies and the emergence of Service Specific Overlay Networks (SSONs), coupled with the rapid development of multimedia applications make the management of such technologies a major challenge. This thesis investigates the SSONs management problem and proposes an autonomic architecture, a self-organizing and self-adapting algorithm, and a utility function for monitoring the Quality of Experience (QoE) of IPTV streams in SSONs. First, we examine the different issues stemming from the autonomic management of SSONs and identify the limitations of existing approaches. We then propose an architecture to ease the management of SSONs by incorporating autonomic computing principles to make SSONs acquire self-management capabilities. The proposed architecture introduces autonomic control loops that continuously monitor network components and analyze the gathered data. An Autonomic System (AS) is comprised of one or more Autonomic Managers (AM) which take control of managing other elements in the network. The proposed architecture highlights the different components of an AM and identifies its purpose. The distributed nature of the proposed architecture avoids limitations of centralized management solutions. We then propose a scheme to allow AMs to emerge among the set of nodes in the network as the most powerful ones in terms of different factors, including processing capabilities and stability. Using a self-organizing and self-adapting distributed protocol, each node in the overlay selects an appropriate AM to report to so that sensed data is delivered error-free, and in a timely manner, while the load is distributed over the AMs. Finally, we propose a utility function to monitor the quality of IPTV streams by predicting QoE based on statistical Quality of Service (QoS) information. The proposed function is simple and does not require high processing power. It allows the QoE of IPTV users to be monitored in real-time by the AMs, so that quality degradations are accurately identified and adaptation mechanisms are triggered at the right moment to correct issues causing degradations. Theoretical analysis and simulations studies are presented to demonstrate the performance of the proposed schemes.
36

Strategické podnikatelské aktivity vybraného podniku / Strategic Business Activities of a chosen Firm

Joštová, Alice January 2009 (has links)
The aim of this thesis is to choose two products of the telecommunication company Telefónica O2 Czech Republic, a.s. - internet ADSL/IPTV, through the sales analysis describe their development,competition, trends on the market etc. and in the end evaluate if it's efficient for the company to continue providing these services or not, choose a the best suitable strategy and simulate probable sales and revenues in 2009, 2010 and 2011. For this running average method will be used.
37

Pokročilé metody postprodukce a distribuce videa s využitím IT / Advanced video post-production and distribution methods using IT

Krist, Antonín January 2010 (has links)
This thesis deals with advanced methods of digital video postproduction and distribution using broadcasting technologies and internet protocol. Describes and compares the distribution methods, using information technology and discusses the current problems. Describes digitization methods and methods that can save bandwidth for distribution. Deals with the possible practical implementation of distribution od three dimensional video to upcoming standards and analyzes the possibilities of their future development. Discusses the overall problems of transmission standardization and advanced video coding. In a conclusion, based on a comparison of methods and practical experience of the author, thesis recommends certain procedures to implement to the standard and specifies the direction of the technological solutions.
38

Sběr dat z velkého počtu počítačů pomocí hierarchické sumarizace / Data acquisition from a great number of computers using hierarchical summarization

Jelínek, Mojmír January 2008 (has links)
This paper deals with IPTV (Internet Protocol Television) transmission of feedback and is showing options and ways of construction, problems and optimalization of signalization protocol. In the beginning are described IPTV and technology terms that this technology uses. Here can be found information about classical TV (Television) transmitting and comparing with IPTV technology, the advantages and disadvantaged of IPTV and answers why this solution has future. Next parts are about history of IPTV and real use over ADSL (Asymmetric Digital Subscriber Line) in present. Here are explained all the necessary units like Head-End, feedback target, root feedback target, ADSL, DSLAM (Digital Subscriber Line Access Multiplexer) and methods of data stream transmission. Also here are described the techniques of video stream compression (MPEG-2 and MPEG-4) and all options of data transmission as broadcast, unicast and multicast. Important part is about transmission speed and needs. The realization also contains applications, written in the C++ language, for transmitting and receiving packets by UDP (User Datagram Protocol) protocol. The task of these applications is to load the main server, where the measurement of packet loss and CPU (Central Processing Unit) load takes place. The result is a table of measured values for specified packet sizes and for specified time intervals between them. The meaning of this measuring is to find the maximal number of computer nodes, which the feedback target is able to proceed. Last part is about realization of 2 applications in JAVA language, which get the information about end-nodes. Both algorithms are using 2 threads to increase speed of getting the information. The client has few random generators within one thread, which will be later replaced by special algorithms for getting real values.
39

Protokol TTP pro správu hierarchických stromů zpětné vazby RTCP kanálu / TTP protocol for managing hierarchy trees of RTCP feedback channel

Müller, Jakub January 2008 (has links)
TTP protocol for managing hierarchy trees of the RTCP feedback channel represents the mechanism for transferring the big amount of data from end users via the “narrow” feedback channel. We are not speaking about thousands of users but about millions of users, which are using services like IPTV. The method of a data summarization is used for this purpose in selected network nodes. The summarized message is transferred and summarized again in higher levels of the hierarchical tree. Both methods allow reducing the amount of data and help to increase information content transferred via the feedback channel. Finding of the correct end user position in a network is also very important aspect. The user must be able to find the closest summarization node with this information and starts sending out the messages to this node for processing. There are several methods for constructing and managing the asynchronous feedback channel that are introduced in this work.
40

Simulační model IPTV služby s protokolem RTP / IPTV multicast model with RTP protocol

Ležák, Aleš January 2008 (has links)
This diploma thesis contains questions of simulation data transfer by ASM multicast. In simulation tool Opnet Modeler is proceed design of service IPTV. IPTV means television which is transfered in network by IP protocol. Data of IPTV service are sending by multicast transfer. Multicast is a technology which uses a group transfer. It is actually communication of a one source of data with many users. These users are receiving the same data. A main target of this technology is to decrement loading of source node and transference system in distribution of data towards group of users. Most often is multicast used in distribution of audiovisual data. Relation RTP/RTCP is simulated with a different numbers of users. Observed is interval of transmission of control RTCP packets. This will be reached by two methods which will be confront in the end. One is a theoretic calculation by course of a equation and second is a practical simulation in Opnet Modeler.

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