Segurança em redes IEEE 802.16: uma visão geral

In order to promote broad adoption of technologies for wireless networks, in addition to reducing costs and ensuring interoperability, diverse organizations as the Institute of Electrical and Electronics Engineers (IEEE), the Internet Engineering Task Force (IETF), the Wireless Ethernet Compatibility Alliance (WECA) and the International Telecommunication Union (ITU) integrate various efforts to standardize. The Institute of Electrical and Electronics Engineers (IEEE) standard 802.16, also known as Worldwide Interoperability for Microwave Access (WIMAX), which defines the air interface and media access methods to Metropolitan Wireless Networks, is being seen, among the technologies which would incorporate the wireless communication in ubiquitous computing environments, as the most promising to access broadband for next generation. This work will present a study about different wireless network standards, including wireless mesh networks and addressing issues of information security and presenting related works that aim to enhance security in these networks.No intuito de promover a ampla adoção de tecnologias de redes sem fio, além de reduzir custos e garantir a interoperabilidade, diversas organizações como o Institute of Electrical and Electronics Engineers (IEEE), a Internet Engineering Task Force (IETF), a Wireless Ethernet Compatibility Alliance (WECA) e a International Telecommunication Union (ITU) integram vários esforços de padronização. O padrão do Institute Electrical and Electronics Engineers (IEEE) 802.16, também conhecido como Worldwide Interoperability for Microwave Access (WIMAX), que define a interface aérea e os métodos de acesso ao meio para Redes Metropolitanas Sem Fio, está sendo visto, dentre as tecnologias que integrarão a comunicação sem fio nos ambientes de computação ubíquos, como a mais promissora para possibilitar o acesso de banda larga de próxima geração. Este trabalho irá apresentar um estudo sobre os diversos padrões de rede sem fio, incluindo as redes sem fio em malha, abordando questões de segurança da informação e apresentando trabalhos relacionados que visam incrementar a segurança nessas redes

Dilma Rousseff: as eleições e a lógica androcêntrica na política brasileira

Com este artigo nos propomos a analisar os modos como as dinâmicas androcêntricas desestabilizam e deslegitimam a presença da mulher no cenário político brasileiro. Para tanto, balizamos nossa análise na emergência eleitoral da candidatura de Dilma Rousseff à presidência da república em 2010. Ao nos centrarmos no percurso eleitoral de Dilma Rousseff, observamos como o trânsito e as participações mantidas pelos diferentes sujeitos na política brasileira assumem configurações diversas, buscando interditar os conhecimentos da mulher e as diferentes formas de entender os espaços e as práticas políticas, afiançando o androcentrismo e a heteronormatividade

ComprehensiveBench: a Benchmark for the Extensive Evaluation of Global Scheduling Algorithms

International audienceParallel applications that present tasks with imbalanced loads or complex communication behavior usually do not exploit the underlying resources of parallel platforms to their full potential. In order to mitigate this issue, global scheduling algorithms are employed. As finding the optimal task distribution is an NP-Hard problem, identifying the most suitable algorithm for a specific scenario and comparing algorithms are not trivial tasks. In this context, this paper presents ComprehensiveBench, a benchmark for global scheduling algorithms that enables the variation of a vast range of parameters that affect performance. ComprehensiveBench can be used to assist in the development and evaluation of new scheduling algorithms, to help choose a specific algorithm for an arbitrary application, to emulate other applications, and to enable statistical tests. We illustrate its use in this paper with an evaluation of Charm++ periodic load balancers that stresses their characteristics

ComprehensiveBench: a Benchmark for the Extensive Evaluation of Global Scheduling Algorithms

International audienceParallel applications that present tasks with imbalanced loads or complex communication behavior usually do not exploit the underlying resources of parallel platforms to their full potential. In order to mitigate this issue, global scheduling algorithms are employed. As finding the optimal task distribution is an NP-Hard problem, identifying the most suitable algorithm for a specific scenario and comparing algorithms are not trivial tasks. In this context, this paper presents ComprehensiveBench, a benchmark for global scheduling algorithms that enables the variation of a vast range of parameters that affect performance. ComprehensiveBench can be used to assist in the development and evaluation of new scheduling algorithms, to help choose a specific algorithm for an arbitrary application, to emulate other applications, and to enable statistical tests. We illustrate its use in this paper with an evaluation of Charm++ periodic load balancers that stresses their characteristics

Energy Efficient Seismic Wave Propagation Simulation on a Low-power Manycore Processor.

International audienceLarge-scale simulation of seismic wave propagation is an active research topic. Its high demand for processing power makes it a good match for High Performance Computing (HPC). Although we have observed a steady increase on the processing capabilities of HPC platforms, their energy efficiency is still lacking behind. In this paper, we analyze the use of a low-power manycore processor, the MPPA-256, for seismic wave propagation simulations. First we look at its peculiar characteristics such as limited amount of on-chip memory and describe the intricate solution we brought forth to deal with this processor's idiosyncrasies. Next, we compare the performance and energy efficiency of seismic wave propagation on MPPA-256 to other commonplace platforms such as general-purpose processors and a GPU. Finally, we wrap up with the conclusion that, even if MPPA-256 presents an increased software development complexity, it can indeed be used as an energy efficient alternative to current HPC platforms, resulting in up to 71% and 5.18x less energy than a GPU and a general-purpose processor, respectively