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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.
1

Deploying Monitoring Trails for Fault Localization in All-optical Networks and Radio-over-Fiber Passive Optical Networks

Maamoun, Khaled M. 24 August 2012 (has links)
Fault localization is the process of realizing the true source of a failure from a set of collected failure notifications. Isolating failure recovery within the network optical domain is necessary to resolve alarm storm problems. The introduction of the monitoring trail (m-trail) has been proven to deliver better performance by employing monitoring resources in a form of optical trails - a monitoring framework that generalizes all the previously reported counterparts. In this dissertation, the m-trail design is explored and a focus is given to the analysis on using m-trails with established lightpaths to achieve fault localization. This process saves network resources by reducing the number of the m-trails required for fault localization and therefore the number of wavelengths used in the network. A novel approach based on Geographic Midpoint Technique, an adapted version of the Chinese Postman’s Problem (CPP) solution and an adapted version of the Traveling Salesman’s Problem (TSP) solution algorithms is introduced. The desirable features of network architectures and the enabling of innovative technologies for delivering future millimeter-waveband (mm-WB) Radio-over-Fiber (RoF) systems for wireless services integrated in a Dense Wavelength Division Multiplexing (DWDM) is proposed in this dissertation. For the conceptual illustration, a DWDM RoF system with channel spacing of 12.5 GHz is considered. The mm-WB Radio Frequency (RF) signal is obtained at each Optical Network Unit (ONU) by simultaneously using optical heterodyning photo detection between two optical carriers. The generated RF modulated signal has a frequency of 12.5 GHz. This RoF system is easy, cost-effective, resistant to laser phase noise and also reduces maintenance needs, in principle. A revision of related RoF network proposals and experiments is also included. A number of models for Passive Optical Networks (PON)/ RoF-PON that combine both innovative and existing ideas along with a number of solutions for m-trail design problem of these models are proposed. The comparison between these models uses the expected survivability function which proved that these models are liable to be implemented in the new and existing PON/ RoF-PON systems. This dissertation is followed by recommendation of possible directions for future research in this area.
2

Deploying Monitoring Trails for Fault Localization in All-optical Networks and Radio-over-Fiber Passive Optical Networks

Maamoun, Khaled M. 24 August 2012 (has links)
Fault localization is the process of realizing the true source of a failure from a set of collected failure notifications. Isolating failure recovery within the network optical domain is necessary to resolve alarm storm problems. The introduction of the monitoring trail (m-trail) has been proven to deliver better performance by employing monitoring resources in a form of optical trails - a monitoring framework that generalizes all the previously reported counterparts. In this dissertation, the m-trail design is explored and a focus is given to the analysis on using m-trails with established lightpaths to achieve fault localization. This process saves network resources by reducing the number of the m-trails required for fault localization and therefore the number of wavelengths used in the network. A novel approach based on Geographic Midpoint Technique, an adapted version of the Chinese Postman’s Problem (CPP) solution and an adapted version of the Traveling Salesman’s Problem (TSP) solution algorithms is introduced. The desirable features of network architectures and the enabling of innovative technologies for delivering future millimeter-waveband (mm-WB) Radio-over-Fiber (RoF) systems for wireless services integrated in a Dense Wavelength Division Multiplexing (DWDM) is proposed in this dissertation. For the conceptual illustration, a DWDM RoF system with channel spacing of 12.5 GHz is considered. The mm-WB Radio Frequency (RF) signal is obtained at each Optical Network Unit (ONU) by simultaneously using optical heterodyning photo detection between two optical carriers. The generated RF modulated signal has a frequency of 12.5 GHz. This RoF system is easy, cost-effective, resistant to laser phase noise and also reduces maintenance needs, in principle. A revision of related RoF network proposals and experiments is also included. A number of models for Passive Optical Networks (PON)/ RoF-PON that combine both innovative and existing ideas along with a number of solutions for m-trail design problem of these models are proposed. The comparison between these models uses the expected survivability function which proved that these models are liable to be implemented in the new and existing PON/ RoF-PON systems. This dissertation is followed by recommendation of possible directions for future research in this area.
3

Deploying Monitoring Trails for Fault Localization in All-optical Networks and Radio-over-Fiber Passive Optical Networks

Maamoun, Khaled M. January 2012 (has links)
Fault localization is the process of realizing the true source of a failure from a set of collected failure notifications. Isolating failure recovery within the network optical domain is necessary to resolve alarm storm problems. The introduction of the monitoring trail (m-trail) has been proven to deliver better performance by employing monitoring resources in a form of optical trails - a monitoring framework that generalizes all the previously reported counterparts. In this dissertation, the m-trail design is explored and a focus is given to the analysis on using m-trails with established lightpaths to achieve fault localization. This process saves network resources by reducing the number of the m-trails required for fault localization and therefore the number of wavelengths used in the network. A novel approach based on Geographic Midpoint Technique, an adapted version of the Chinese Postman’s Problem (CPP) solution and an adapted version of the Traveling Salesman’s Problem (TSP) solution algorithms is introduced. The desirable features of network architectures and the enabling of innovative technologies for delivering future millimeter-waveband (mm-WB) Radio-over-Fiber (RoF) systems for wireless services integrated in a Dense Wavelength Division Multiplexing (DWDM) is proposed in this dissertation. For the conceptual illustration, a DWDM RoF system with channel spacing of 12.5 GHz is considered. The mm-WB Radio Frequency (RF) signal is obtained at each Optical Network Unit (ONU) by simultaneously using optical heterodyning photo detection between two optical carriers. The generated RF modulated signal has a frequency of 12.5 GHz. This RoF system is easy, cost-effective, resistant to laser phase noise and also reduces maintenance needs, in principle. A revision of related RoF network proposals and experiments is also included. A number of models for Passive Optical Networks (PON)/ RoF-PON that combine both innovative and existing ideas along with a number of solutions for m-trail design problem of these models are proposed. The comparison between these models uses the expected survivability function which proved that these models are liable to be implemented in the new and existing PON/ RoF-PON systems. This dissertation is followed by recommendation of possible directions for future research in this area.
4

Transporte TDM em redes GPON / TDM transport in GPON networks

Guimarães, Marcelo Alves 17 February 2011 (has links)
Neste trabalho analisamos e propomos a utilização de TDM (Time Division Multiplexing) nativo canalizado/estruturado em redes PON (Passive Optical Network) com padrão GPON (Gigabit Passive Optical Network), com ênfase na estrutura de transmissão do legado das redes de telefonia. O objetivo principal é obter um aumento na eficiência de banda transmitida através da fragmentação de sinais E1 sem que seja necessário o uso de técnicas de emulação de circuito (que reduzem a eficiência de banda devido à adição de cabeçalhos). Inicialmente, é descrito o transporte TDM em redes GPON, como efetuado pelos equipamentos comerciais atuais através de duas técnicas: CES - Circuit Emulation Service e TDM nativo não estruturado. Em seguida, é introduzido o conceito de comutação digital visando sua aplicação no transporte TDM nativo estruturado em redes GPON. Nesta etapa, é proposta uma solução para este transporte, é descrito o protocolo utilizado bem como seu funcionamento. Por fim, como prova de conceito, é apresentada uma implementação em HDL (Hardware Description Language) para FPGA (Field Programmable Gate Array). / In this work we analyze and propose the use of native channeled /structured TDM (Time Division Multiplexing) in GPON (Gigabit Passive Optical Network), with emphasis on the structure for transmission of the telephone network legacy. The main target is to achieve an increase in transmitted bandwidth efficiency by fragmenting E1 signals, thus avoiding the use of circuit emulation techniques (which reduce the bandwidth efficiency due to overhead addition). Initially, it is described in TDM transport in GPON networks, as it is performed in present commercial equipment by two techniques: CES - Circuit Emulation Service and Native TDM - unstructured. Next, we introduce the concepts of digital switching aiming its application on the transport of native and structured TDM in GPON. At this stage, we propose a transport solution, describe its protocol and functionalities. Finally, for concept proof, we present an implementation in HDL (Hardware Description Language) meant to FPGA (Field Programmable Gate Array) application.
5

Transporte TDM em redes GPON / TDM transport in GPON networks

Marcelo Alves Guimarães 17 February 2011 (has links)
Neste trabalho analisamos e propomos a utilização de TDM (Time Division Multiplexing) nativo canalizado/estruturado em redes PON (Passive Optical Network) com padrão GPON (Gigabit Passive Optical Network), com ênfase na estrutura de transmissão do legado das redes de telefonia. O objetivo principal é obter um aumento na eficiência de banda transmitida através da fragmentação de sinais E1 sem que seja necessário o uso de técnicas de emulação de circuito (que reduzem a eficiência de banda devido à adição de cabeçalhos). Inicialmente, é descrito o transporte TDM em redes GPON, como efetuado pelos equipamentos comerciais atuais através de duas técnicas: CES - Circuit Emulation Service e TDM nativo não estruturado. Em seguida, é introduzido o conceito de comutação digital visando sua aplicação no transporte TDM nativo estruturado em redes GPON. Nesta etapa, é proposta uma solução para este transporte, é descrito o protocolo utilizado bem como seu funcionamento. Por fim, como prova de conceito, é apresentada uma implementação em HDL (Hardware Description Language) para FPGA (Field Programmable Gate Array). / In this work we analyze and propose the use of native channeled /structured TDM (Time Division Multiplexing) in GPON (Gigabit Passive Optical Network), with emphasis on the structure for transmission of the telephone network legacy. The main target is to achieve an increase in transmitted bandwidth efficiency by fragmenting E1 signals, thus avoiding the use of circuit emulation techniques (which reduce the bandwidth efficiency due to overhead addition). Initially, it is described in TDM transport in GPON networks, as it is performed in present commercial equipment by two techniques: CES - Circuit Emulation Service and Native TDM - unstructured. Next, we introduce the concepts of digital switching aiming its application on the transport of native and structured TDM in GPON. At this stage, we propose a transport solution, describe its protocol and functionalities. Finally, for concept proof, we present an implementation in HDL (Hardware Description Language) meant to FPGA (Field Programmable Gate Array) application.
6

Introduction des technologies de multiplexage en longueur d'onde dense dans les futures générations de réseaux d'accès optique / Dense wavelength division multiplexing technologies introduction in futures optical access networks generations

Simon, Gaël 01 December 2016 (has links)
Initialement poussées par le marché résidentiel, les évolutions du réseau d’accès optique sont aujourd’hui également stimulées par l’expansion du réseau mobile. Comme le montre le premier chapitre de ce document, l’introduction d’un multiplexage en longueur d’onde dense constitue l’une des solutions privilégiées pour permettre la montée en débit dans les réseaux d’accès optique. Dans cette thèse, l’impact de l’introduction du multiplexage en longueur d’onde dense est étudié sous trois axes :• Une prochaine étape de l’évolution des technologies pour les réseaux d’accès passerait par une hybridation entre d’une part, un multiplexage temporel (hérité des précédentes générations), et d’autre part, un multiplexage en longueur d’onde dense. Cette technologie, appelée NGPON2-TWDM, permet aujourd’hui d’envisager des débits de 40Gb/s à 80Gb/s grâce à 4 ou 8 canaux. Les difficultés liées à la stabilité de la longueur d’onde lors de l’émission de données en mode paquet dans le sens montant du lien, ainsi que les solutions associées, sont étudiées dans le second chapitre.• L’importance du marché que représente le réseau d’accès optique (aussi bien pour les clients résidentiels que pour les réseaux mobiles), induit la nécessité pour les différentes générations de technologies de coexister au sein d’une même infrastructure. Du fait des fortes puissances optiques en jeu et des plages spectrales allouées à chaque technologie, cette coexistence peut induire des interactions entre technologies par émission Raman stimulée, dont le principe et les impacts sont décrits dans le troisième chapitre.• Enfin, la quatrième partie de ce document est dédiée à l’étude des limites et potentialités de la technologie self-seeded pour le multiplexage en longueur d’onde dense en bande O, capable de stabiliser automatiquement et passivement la longueur d’onde d’émission de chacun des émetteurs du système. / Initially led by the residential market, today’s optical access network evolutions are stimulated by mobile network expansion. As shown in the first chapter of this document, dense wavelength division multiplexing is one of the favorite solutions in order to increase optical access networks throughput. In this thesis, we propose a study of dense wavelength division multiplexing introduction according to three main topics :• Service providers and equipment suppliers have decided that the next step in residential market evolution will consist in a hybridization between, on one hand, a legacy time division multiplexing, and on the other hand, a dense wavelength division multiplexing. Named NG-PON2, this technology allows today 40Gb/s to 80Gb/s thanks to 4 to 8 channel pairs. Wavelength stability of the upstream emitter under burst mode operation, and related solutions, are studied in the second chapter.• Market importance (for both residential market and mobile networks) requires the different technologies generations to coexist on the same infrastructure. Due to the high optical power and the wavelength spans allocated to each technology, this coexistence can lead to technologies interactions by stimulated Raman scattering, as described in the third chapter.• Finally, the fourth part of this document describes the limits and potentialities of the self-seeded emitter technology for O-band dense wavelength division multiplexing, able to automatically and passively self-stabilize the wavelength of each emitter.

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