Modeling an Optical Network Operating with Hybrid-Switching Paradigms

Abstract The continuous increasing of the Internet traffic has brought serious concerns about capacity exhaustion of the optical infrastructure in a medium term horizon. Taking into account the optical networks, comprising the Internet backbone, the strategies to avoid this catastrophic scenario point to the development of new technologies that enable the capacity expansion, as well as to a better utilization of network resources (spectrum or wavelengths). The elastic optical network, considered as a realistic perspective for the infrastructure, optimizes the required spectrum and improve the efficiency of resources utilization. However, it is based on optical circuit switching paradigm that tends to waste resources due to idle times of reservation process. Since in some dedicated optical networks, like data center networks, certain optical switching paradigms have become reality, it is expected that in the coming years not only an elastic optical network, but also a hybrid network, in terms of switching paradigms, be brought to reality. Considering this scenario, the present paper addresses some issues on the modeling of an optical network working with hybrid-switching paradigms

An innovative architecture proposal for optical packet networks based on photonic switching

Orientadores: Edson Moschim, Felipe Rudge BarbosaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de ComputaçãoResumo: Hoje em dia, como uma multiplicidade muito grande de tecnologias converge para as redes fotônicas, a demanda por vazão cresce. Os protocolos para acesso múltiplo e simultâneo às portas de entrada da rede, bem como a abordagem do formato dos pacotes fotônicos e a arquitetura das redes, são considerados como alternativas tecnológicas para a melhora do desempenho das redes fotônicas. Deste modo, apresenta-se aqui uma proposta para a arquitetura de redes fotônicas,utilizando topologias em malha otimizadas para que os pacotes atinjam seus respectivos nós de destino no menor número de hops possível, com nós de rede 2x2. Além disso, utiliza-se o roteamento por deflexão para a resolução de contenda entre pacotes ópticos, bem como buffers eletrônicos na entrada da rede óptica para evitar problemas de perdas de inserção. Além disso, a estrutura de rede permite hierarquização e também se propõe um modelo para o funcionamento do nó que faz a ligação entre hierarquias diferentes dentro da rede óptica. Esta arquitetura de rede é então avaliada quanto à sua capacidade de prover requisitos para QoS em termos de perdas de pacotes, atrasos e inversão de ordem de pacotes, para a qual é proposta uma heurística para uma avaliação quantitativa. Os resultados mostram que uma arquitetura nos moldes apresentados é capaz de prover ganhos de desempenho, oferecendo condições para a garantia de QoS, provida por protocolos de rede em nível superior, até cerca de 70% de cargaAbstract: Nowadays, as a multiplicity of technologies converges upon the optical network, the demand for throughput increases. The protocols for multiple and simultaneous access to network ports, as well as the optical packet approach should be considered as technological alternatives to optical network performance upgrade. Thus, we present here a new proposal to the architecture of optical packet networks, using mesh topologies optimized in such a way that the packets reach their respective destination nodes with the smaller possible number of hops, and using 2x2 network nodes. Besides, we use deflection routing to solve the contention between optical packets, as well as electronical buffers at the optical network input to prevent problems with insertion losses. The structure of the network also allows hierarchization, performing the link between different hierarchies on the optical network. The performance of the proposed architecture is evaluated by the capacity of providing requirements of QoS, in terms of packet losses, delays and the amount of out of order packets, for which is presented a heuristic to get a quantitative estimation. The results show that the proposed architecture is able to provide performance gains, giving conditions to guarantee some levels of QoS, which is done by the specific protocols of superior network layers, up to 70% of network loadDoutoradoTelecomunicações e TelemáticaDoutor em Engenharia Elétric

Contribuição ao estudo de redes fotonicas de pacotes

Orientadores : Edson Moschim, Mario Tosi FurtadoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de ComputaçãoMestrad

Why optical packet switching failed and can elastic optical networks take its place?

In this special issue devoted to the memory of Prof. Fabio Neri we would like to look back at the time of the international research projects where some of us collaborated with him. On the basis of our personal experience of the time and the current viewpoint, we will discuss why Optical Packet Switching (OPS) is a technology that never came to market in spite of the great amount of research that was devoted to it. Then we will explore how Elastic Optical Network came to the stage more recently, somewhat overcoming the OPS technical proposal both in the interest of the researchers as well as of the industry

Núcleos de Ensino da Unesp: artigos 2008

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq