The dinamicy and uncertainness of resources in mobile networks ask for novel uncoupled, adaptable and autonomous programming abstractions. Although applications are built upon a middleware layer that encapsulates some of that complexity, there is a lot left to fully explore the potential of ubiquitous and pervasive systems. To provide an insight on the challenges to develop interoperable middleware systems, this paper highlights the requirements to build serviceoriented ubiquitous and pervasive middleware. These requirements are divided into primary and cross-cutting requirements. Primary requirements are Message Exchange,
Sensors of all kinds are being integrated with mobile and portable devices (tablets, smartphones). This opens up the possibility of context-aware applications to effectively be able to adapt their behavior, user interfaces and content according to the current user's situation. Frequently, contextaware applications require an infrastructure for acquisition, aggregation and reasoning of contextual information. However, existing context management infrastructures are not always appropriated to the heterogeneous and particular environment of mobile devices. In this paper, we present a context management middleware called LoCCAM (Loosely Coupled Context Acquisition Middeware) to provide selfadaptive acquisition of contextual information. It can execute both locally, on a single device, or distributed among nearby devices. The middleware proposes a model for publication, and notification of contextual information based on tuple spaces. As consequence, it offers a lower coupling among applications and the context acquisition layer. In this paper, we also present a performance evaluation of the adaptation mechanism. * CNPq Master Scholarship (MDCC/DC/UFC) † CAPES Master Scholarship (MDCC/DC/UFC) ‡ CNPq Research Scholarship (process
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