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The SIDAM Project

We are currently engaged in a research project called SIDAM [4]. SIDAM stands for Distributed Information Systems for Mobile Agents. The research aims at studying the main problems related to the design and implementation of decentralized information systems for mobile users. As a reference application it uses an on-line system for disseminating road traffic information, but the model is generic enough to be applied to a wide spectrum of applications. The SIDAM reference application is a distributed information service disseminating road traffic information for a large metropolis, such as São Paulo, Tokyo, or New York. The service can be queried and updated by mobile users, who may be either common citizens requiring information about the traffic situation in a specific part of a city or may be the São Paulo Traffic Engineering Company (CET) staff, feeding the system with data about the traffic. In order to keep the size of the information base and the corresponding queries manageable, the SIDAM application divides the city into micro-regions (e.g., a few blocks) that are the atomic units holding traffic information. The micro-regions traffic data are stored at Information Servers (IS). Each information server can hold data from one or more micro-regions. Information servers reside at Data Servers, which are fixed hosts. The SIDAM reference architecture is a interesting example of a highly dynamic and distributed application since the generation, storage and query of information are decentralized and clients are mobile. In this case, adaptation becomes essential for achieving high service availability, dynamic load balancing and near optimal response times for clients.
next up previous
Next: Main Objective and Related Up: Problem Description Previous: Problem Description
Francisco Jose da Silva e Silva 2001-09-24