No abstract

A large number of performance evaluation tools have been developed over the years to support the analyst in the difficult task of model building. As systems increase in complexity, the need is critical for tools that are able to help the user throughout the whole modeling cycle, from model building to model solution and experimentation. In this work we describe the main features of the TANGRAM-II modeling environment. The tool has a powerful and flexible model interface, unique algorithms for the numerical solution of models, includes an event driven and fluid simulators that provides a variety of facilities useful for obtaining the measures of interest, and has a traffic engineering environment integrated with the other tool modules.

In this paper, we present our experience to estimate the reliability of a large distributed system composed of several hundred points of presence. The system's reliability metric is required by contract to be obtained. A simple approach is presented to accurately approximate the desired metrics.

The One Laptop per Child (OLPC) is a model that aims to transform the learning process of every child in developing countries through Information and Communications Technology (ICT). However, cultural, economic and social diversities make each model implementation unique. This study analyses the application of OLPC in Uruguay and Brazil. It aims to understand and describe common aspects that are important to the success of this kind of implementation. Our goal is to contribute with future projects that use ICT to transform the way that children learn.Resumo. O One Laptop per Child (OLPC) é uma proposta cujo objetivo busca, através do uso da Tecnologia de Informação e Comunicação (TIC), transformar o processo de aprendizagem de todas as crianças em países de desenvolvimento. Entretanto, as diversidades culturais, econômicas e sociais fazem com que cada implementação seja única. O presente trabalho faz uma análise crítica sobre a aplicação do OLPC no Uruguai e no Brasil. Procura evidenciar aspectos comuns que sejam importantes para aplicação dessa proposta. Com isso, esperamos contribuir com novos projetos que objetivem transformar o processo de ensino e aprendizagem através do uso das TICs.

Resumo-O custo de uma rede de comunicações IP pode ser entendido como o custo financeiro de contratação da banda requerida ou, no caso de uma rede própria, o custo financeiro de manutenção dos cabos, fibras e equipamentos para determinadas capacidades dos enlaces. O objetivo deste trabalho é dimensionar uma rede IP garantindo o menor custo possível mas ao mesmo tempo garantido a qualidade de serviço (QoS) contratada pelos clientes desta rede.