Controle de conexões, sinalizações e fluxos de células em uma rede ATM utilizando Java e SNMP

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico.A finalidade deste trabalho é apresentar um módulo de gerência para o controle de conexões, sinalizações e fluxos de células em uma rede ATM. Este módulo utiliza a simplicidade do protocolo SNMP e as facilidades disponíveis na linguagem de programação Java para permitir o gerenciamento dos fluxos de células em SVCs, bem como realizar um levantamento sobre todas as conexões ativas em um comutador, classificando-as como ponto a ponto ou ponto a multiponto. Além disso, é possível obter as informações sobre as sinalizações ATM

Implementação de um ambiente de gerência em redes ATM utilizando a tecnologia WEB /

Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico.A proposta deste trabalho foi implementar um ambiente de gerência para redes ATM (Asynchronous Transfer Mode) integrado com a tecnologia Web. Para essa finalidade, elaborou-se um estudo detalhado das variáveis das MIBs (Management Information Base) de gerência relativas à parâmetros de tráfego e conexões virtuais das redes ATM. Tais variáveis foram relacionadas com as questões teóricas de tráfego, estabelecimento de conexões e a monitoração de alguns recursos vitais para o funcionamento dessas redes. Através deste estudo, implementou-se um ambiente de gerência que pode ser utilizado tanto pelo gerente da rede, com a finalidade de controlar a utilização de recursos, quanto pelos usuários finais, com a finalidade de obter históricos sobre essa utilização. Tal facilidade é oferecida pela implementação em código Java, que tornou possível que a ferramenta seja utilizada a partir de qualquer ponto da Internet que possua um browser Web

System architecture and hardware implementations for a reconfigurable MPLS router

With extremely wide bandwidth and good channel properties, optical fibers have brought fast and reliable data transmission to today’s data communications. However, to handle heavy traffic flowing through optical physical links, much faster processing speed is required or else congestion can take place at network nodes. Also, to provide people with voice, data and all categories of multimedia services, distinguishing between different data flows is a requirement. To address these router performance, Quality of Service /Class of Service and traffic engineering issues, Multi-Protocol Label Switching (MPLS) was proposed for IP-based Internetworks. In addition, routers flexible in hardware architecture in order to support ever-evolving protocols and services without causing big infrastructure modification or replacement are also desirable. Therefore, reconfigurable hardware implementation of MPLS was proposed in this project to obtain the overall fast processing speed at network nodes. The long-term goal of this project is to develop a reconfigurable MPLS router, which uniquely integrates the best features of operations being conducted in software and in run-time-reconfigurable hardware. The scope of this thesis includes system architecture and service algorithm considerations, Verilog coding and testing for an actual device. The hardware and software co-design technique was used to partition and schedule the protocol code for execution on both a general-purpose processor and stream-based hardware. A novel RPS scheme that is practically easy to build and can realize pipelined packet-by-packet data transfer at each output was proposed to take the place of the traditional crossbar switching. In RPS, packets with variable lengths can be switched intelligently without performing packet segmentation and reassembly. Primary theoretical analysis of queuing issues was discussed and an improved multiple queue service scheduling policy UD-WRR was proposed, which can reduce packet-waiting time without sacrificing the performance. In order to have the tests carried out appropriately, dedicated circuitry for the MPLS functional block to interface a specific MAC chip was implemented as well. The hardware designs for all functions were realized with a single Field Programmable Gate Array (FPGA) device in this project. The main result presented in this thesis was the MPLS function implementation realizing a major part of layer three routing at the reconfigurable hardware level, which advanced a great step towards the goal of building a router that is both fast and flexible

Evolution and usability of mobile phone interaction styles

Over one billion people own or use cellular mobile telephones. Therefore, industry practitioners are faced with a question: how big steps can they take when designing the user interfaces for their new products, or how closely should they stick with the already existing user interface conventions that may already be familiar to the consumers. The objective of this research work is to create and communicate new knowledge for design and usability practitioners about how to design and evolve interaction style conventions in mainstream, voice-centric mobile telephones. In the context of this study, interaction style denotes the framework consisting of the physical interaction objects, the abstract interaction elements, and the associated behavior or interaction conventions that are applied throughout the core functionality of the mobile phone, but excludes the stylistic appearance elements of the user interface. The main research problem — how do mobile phone interaction style changes affect the initial usability of a mobile phone for users with earlier experience with mobile phones — is approached via several methods. A literature study compares the interaction styles applied in mainstream computing domains against the aspects relevant in the mobile phones domain. A heuristic analysis of contemporary mobile phones is used to formulate an understanding of the available interaction styles and analyze whether there is convergence towards specific types of interaction styles in the industry. An empirical usability testing experiment with 38 test users is conducted with a novel mobile phone interaction style to investigate differences between users who are already familiar with different mobile phone interaction styles. The study reveals that interaction styles applied in contemporary mobile telephones are designed around menu navigation, and they implement the three primary operations — Select, Back and Menu access — with dedicated hardkeys, context-sensitive softkeys, or using special control devices like joysticks or jog dials. The control keys in the contemporary interaction styles are converging around various two- and three-softkey conventions. The aspects related to indirect manipulation and small displays pose specific usability and UI design challenges on mobile phone user interfaces. The study shows that the mobile handset manufacturers are applying their usually proprietary interaction styles in a rather consistent manner in their products, with the notable exception of mobile Internet browsers that often break the underlying interaction style consistency. Based on the results from the empirical usability testing, we claim that despite differences between interaction styles in contemporary mobile phones, users do not face significant difficulties when transferring to a novel mobile phone model.reviewe

Optoelectronics – Devices and Applications

Optoelectronics - Devices and Applications is the second part of an edited anthology on the multifaced areas of optoelectronics by a selected group of authors including promising novices to experts in the field. Photonics and optoelectronics are making an impact multiple times as the semiconductor revolution made on the quality of our life. In telecommunication, entertainment devices, computational techniques, clean energy harvesting, medical instrumentation, materials and device characterization and scores of other areas of R&D the science of optics and electronics get coupled by fine technology advances to make incredibly large strides. The technology of light has advanced to a stage where disciplines sans boundaries are finding it indispensable. New design concepts are fast emerging and being tested and applications developed in an unimaginable pace and speed. The wide spectrum of topics related to optoelectronics and photonics presented here is sure to make this collection of essays extremely useful to students and other stake holders in the field such as researchers and device designers