Navegando por Data de Publicação, começando com "2007-06-21"

Filtrar resultados por ano ou mês

Agora exibindo 1 - 2 de 2

Uma arquitetura de proxy com prioridades de serviços para chamadas remotas de procedimentos de tempo real
(Universidade Federal de São Carlos, 2007-06-21) Nobile, Pedro Northon; Trevelin, Luis Carlos; https://lattes.cnpq.br/5082419783043736; https://lattes.cnpq.br/1286000431921559
During the last few years is possible to observ an significant increase of real time applications, , mainly of multimedia applications (e.g. video and voice streamming). Factors such as the popularization of broadband (e.g. XDSL) and wireless (e.g. 802.11 familiy and 802.15 pattern) networks, associated to the appearance of better devices and the increase of user s communications need, have contributed. Currently, with the appearance of new concepts of communications like home networks, it is possible to predict that real time applications will be part of user s daily. Anticipating a solution to that predict, this work proposes a proxy architecture with priorities of services for real time remote procedure calls, that uses the earlier amount of tra_c to predict the future occupation network, and choose the most appropriate policy to adapt the proxy to the environment future states.
Protocolos de roteamento cientes de QoS para redes de sensores e atuadores sem fio
(Universidade Federal de São Carlos, 2007-06-21) Villas, Leandro Aparecido; Araujo, Regina Borges de; https://lattes.cnpq.br/8964123297688432; https://lattes.cnpq.br/9830590737740134
Wireless sensor networks are increasingly being deployed for fine-grain monitoring of physical environments subjected to critical conditions such as fire, leaking of toxic gases and explosions. A great challenge to these networks is to provide channels that satisfy the necessities of the applications for events propagation, even in the presence of emergency conditions that can lead to node failures and path disruption to the sink that receives those events. Quality of Service (QoS) mechanisms can be applied that meet application requirements such as: low latency and packet delivery reliability, fast path repair in the presence of faults and network longevity with uniform energy dissipation. This work presents QoS-based routing solutions, which aims to meet, simultaneously, the main requirements mentioned above. The proposed solutions were implemented and simulated in the NS-2 simulator. Important metrics, such as end-to-end delay, packet loss rate, control messages overhead and energy consumption, were evaluated. The results show that the proposed solutions can be a potential alternative to the supervision and control of physical environments subject to emergency situations