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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

Formulação algébrica para a modelagem de algoritmos de roteamento multi-restritivo hop-by-hop. / Algebraic formulation for modeling hop-by-hop multi-constrained routing algorithms.

Herman, Walmara de Paula 04 April 2008 (has links)
Este trabalho apresenta uma nova estrutura matemática para a álgebra de caminhos, que permite analisar a convergência dos algoritmos de roteamento multi-restritivos hop-by-hop e, sob o ponto de vista da engenharia de tráfego e da Qualidade de Serviço (QoS) na arquitetura Generalized Multiprotocol Label Switching (GMPLS), garantir de maneira confiável a incorporação de novas métricas de roteamento aos algoritmos de roteamento baseados em múltiplas restrições. Baseando-se nessa nova álgebra de caminhos, são analisadas as propriedades de monotonicidade, isotonicidade e liberdade, conhecidas por garantir a convergência dos algoritmos de roteamento e, ao contrário do indicado na literatura até o momento, verifica-se que a propriedade de monotonicidade não e condição necessária e nem suficiente para garantir a convergência dos algoritmos de roteamento multi-restritivos hop-by-hop. Sendo assim, este trabalho propõe uma nova propriedade, denominada coerência, para a garantia da convergência do roteamento hop-by-hop e um novo algoritmo de roteamento hop-by-hop com convergência garantida. Para avaliar os resultados teóricos obtidos, s~ao analisados dois estudos de casos de aplicação do roteamento multi-restritivos hop-by-hop com o uso de uma ferramenta de simulação desenvolvida em MATLAB e baseada no algoritmo Eliminação de Loop pelo Nó de Destino (ELND) também proposto. Como resultado das simulações desses estudos de casos, verifica-se que as diferentes estratégias de otimização, necessárias as redes (GMPLS), impõem a necessidade de trabalhar com algoritmos de roteamento que permitam a definição de mais de duas métricas de roteamento com diferentes critérios de otimização para cada uma delas, comprovando, portanto, a necessidade do desenvolvimento e da continuação deste trabalho. / This work presents a new mathematical structure for paths algebra that allows the convergence analysis of hop-by-hop multi-constrained routing algorithms and, under the traffic engineering and quality of service perspectives in the Generalized Multiprotocol Label Switching (GMPLS) architecture, trustily ensures the aggregation of new routing metrics in a constrained-based routing. Based on this new paths algebra, we analyze the monotonicity, isotonicity and freeness properties, known as ensuring routing algorithms convergence, and despite of what has been indicated in the literature, we verified that the monotonicity property is not sufficient to ensure the hop-by-hop routing convergence. Therefore, this work proposes a new property, called coherence, as a necessary and sufficient condition to ensure it, as well as, a new multi-constrained hop-by-hop routing algorithm with ensured convergence. In order to evaluate the theoretical results obtained, two study cases of the hop-by-hop multi-constrained routing applications are analyzed in the present thesis by using the Eliminação de Loop pelo Nó de Destino (ELND) simulation tool, developed in MATLAB and also presented as a product of this work. As result of these study cases simulations, we verified that different optimization strategies, requested by the (GMPLS) networks, compel the use of routing algorithms that allow the specification of more than two routing metrics with different optimization criteria for each one of them, thus proving the necessity of this work and its continuation.
2

Formulação algébrica para a modelagem de algoritmos de roteamento multi-restritivo hop-by-hop. / Algebraic formulation for modeling hop-by-hop multi-constrained routing algorithms.

Walmara de Paula Herman 04 April 2008 (has links)
Este trabalho apresenta uma nova estrutura matemática para a álgebra de caminhos, que permite analisar a convergência dos algoritmos de roteamento multi-restritivos hop-by-hop e, sob o ponto de vista da engenharia de tráfego e da Qualidade de Serviço (QoS) na arquitetura Generalized Multiprotocol Label Switching (GMPLS), garantir de maneira confiável a incorporação de novas métricas de roteamento aos algoritmos de roteamento baseados em múltiplas restrições. Baseando-se nessa nova álgebra de caminhos, são analisadas as propriedades de monotonicidade, isotonicidade e liberdade, conhecidas por garantir a convergência dos algoritmos de roteamento e, ao contrário do indicado na literatura até o momento, verifica-se que a propriedade de monotonicidade não e condição necessária e nem suficiente para garantir a convergência dos algoritmos de roteamento multi-restritivos hop-by-hop. Sendo assim, este trabalho propõe uma nova propriedade, denominada coerência, para a garantia da convergência do roteamento hop-by-hop e um novo algoritmo de roteamento hop-by-hop com convergência garantida. Para avaliar os resultados teóricos obtidos, s~ao analisados dois estudos de casos de aplicação do roteamento multi-restritivos hop-by-hop com o uso de uma ferramenta de simulação desenvolvida em MATLAB e baseada no algoritmo Eliminação de Loop pelo Nó de Destino (ELND) também proposto. Como resultado das simulações desses estudos de casos, verifica-se que as diferentes estratégias de otimização, necessárias as redes (GMPLS), impõem a necessidade de trabalhar com algoritmos de roteamento que permitam a definição de mais de duas métricas de roteamento com diferentes critérios de otimização para cada uma delas, comprovando, portanto, a necessidade do desenvolvimento e da continuação deste trabalho. / This work presents a new mathematical structure for paths algebra that allows the convergence analysis of hop-by-hop multi-constrained routing algorithms and, under the traffic engineering and quality of service perspectives in the Generalized Multiprotocol Label Switching (GMPLS) architecture, trustily ensures the aggregation of new routing metrics in a constrained-based routing. Based on this new paths algebra, we analyze the monotonicity, isotonicity and freeness properties, known as ensuring routing algorithms convergence, and despite of what has been indicated in the literature, we verified that the monotonicity property is not sufficient to ensure the hop-by-hop routing convergence. Therefore, this work proposes a new property, called coherence, as a necessary and sufficient condition to ensure it, as well as, a new multi-constrained hop-by-hop routing algorithm with ensured convergence. In order to evaluate the theoretical results obtained, two study cases of the hop-by-hop multi-constrained routing applications are analyzed in the present thesis by using the Eliminação de Loop pelo Nó de Destino (ELND) simulation tool, developed in MATLAB and also presented as a product of this work. As result of these study cases simulations, we verified that different optimization strategies, requested by the (GMPLS) networks, compel the use of routing algorithms that allow the specification of more than two routing metrics with different optimization criteria for each one of them, thus proving the necessity of this work and its continuation.
3

Priorty Based Multi-constraint Qualty Of Service Routing In Military Applications

Araz, Bora 01 September 2005 (has links) (PDF)
This thesis proposes a new algorithm for multi-constrained Quality of Service Optimal Path Routing in the context of military applications. The objective of our routing algorithm is to manage network traffic according to quality of service requirements of connection requests using military metrics. The algorithm is mainly based on communication priority. The QoS metrics such as bandwidth, delay and packet loss ratio are considered as basic metrics on path finding. If there is no suitable path for the request, some existing connections with lower priorities may be broken to make space for a higher priority level connection request. In this case, priority and bandwidth are used as decisive metrics in cost computation
4

Allocation conjointe des canaux de fréquence et des créneaux de temps et routage avec QdS dans les réseaux de capteurs sans fil denses et étendus / Joint allocation of channels of frequency and time slots with QoS routing for large-scale Wireless Sensor Networks

Ben Slimane, Jamila 12 March 2013 (has links)
Le thème général du sujet tourne autour de l'optimisation inter-couche des réseaux de capteurs basés sur la technologie ultra large bande ULB (UWB, Ultra Wide Band) moyennant des solutions protocolaires permettant d'un côté de répondre au besoin de qualité de service QdS à critères multiples dans les réseaux de capteurs sans fil et d'autre côté d'assurer le partage et l'allocation efficace les ressources disponibles (spectrale et temporelle) ainsi que l'optimisation de la consommation d'énergie dans des tels réseaux. Le domaine d'application cible choisi dans le présent travail est les systèmes de suivi des patients au sein d'un réseau de capteurs déployé en hôpital intelligent (WHSN, Large-scale Wireless Hospital Sensor Network). Dans ce contexte, nous avons proposé le modèle UWBCAS pour assurer le partage des ressources spectrales entre les PANs. Puis, nous avons conçu et implémenté un protocole MAC multi-canal multi-créneau de temps avec support de qualité de service, PMCMTP, pour assurer une allocation conjointe des canaux de fréquence et des créneaux de temps au sein de chaque réseau PAN. Enfin nous avons proposé l'algorithme JSAR qui traite à la fois les problèmes d'ordonnancement des cycles d'activités des membres du réseau dans le but d'optimiser la consommation d'énergie, d'allocation efficace des canaux de fréquence et des créneaux de temps afin d'améliorer le taux d'utilisation des ressources et les performances du réseau et de routage avec support de QdS à critères multiples afin de répondre aux besoins des applications supportées / The general context of the present memory is about the cross-layer optimization of wireless sensors networks based on ultra wide band technology UWB. The proposed solutions ensure the share and the efficient allocation of spectral and temporal resources, the optimization of the energy consumption and the support of multi-constraints quality of services QoS. The most challenging issue is providing a tradeoff between the resource efficiency and the multiconstrained QoS support. For this purpose, we proposed a new Wireless Hospital Sensor Network (WHSN) three-tiered architecture in order to support large-scale deployment and to improve the network performance. Then we designed a channel allocation scheme (UWBCAS,)and a prioritized multi-channel multi-time slot MAC protocol (PMCMTP) to enhance network performance and maximize the resource utilization. Finally, we proposed a joint duty cycle scheduling, resource allocation and multi-constrained QoS routing algorithm (JSAR) which simultaneously combines, a duty cycle scheduling scheme for energy saving, a resource allocation scheme for efficient use of frequency channels and time slots, and an heuristic for multi-constrained routing protocol

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