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Novel ubiquitous computing applications such as intelligent vehicles, smart buildings, and traffic management require special properties that traditional computing applications do not support, such as context-awareness, massive decentralisation, autonomous behaviour, adaptivity, proactivity, and innate collaboration. This paper presents a new computational model and middleware that reflect support for the required the properties. The sentient object model is proposed by the CORTEX project to support the construction of ubiquitous applications. A flexible, run-time reconfigurable component-based middleware has been built to provide run-time support to engineer the sentient object programming paradigm. An application infrastructure using sentient objects to enable cooperation between autonomous and proactive vehicles has been implemented to demonstrate the appropriateness of the computational model and the validity of the middleware for pervasive mobile ad hoc computing.

It is becoming clear that location-aware intelligent transportation systems will be one of the most promising upcoming applications for next generation vehicles. The driving force behind this is the introduction of pervasive high performance wireless networks and location sensing technologies, such as GPS and roadside detection systems. Intelligent transportation systems utilise inter-vehicle cooperation without human assistance to provide autonomous vehicle navigation from a given source to a predetermined destination. The resultant sentient vehicles are 'context-aware' autonomous cars that form cooperative 'flotillas' of peers using mobile ad hoc network environments (MANETs). In this paper we report on our experiences of building a component framework based middleware architecture designed to meet the challenges of such environments. We show how such a framework can be used to engineer a proof of concept cooperating sentient vehicle application, and highlight the research challenges raised.

With advances in sensor-based computing and mobile communication, people have started to explore ubiquitous or pervasive computing systems that aim to have computing devices literally available everywhere, making them disappear into the physical environment. Novel ubiquitous computing applications such as intelligent vehicles, smart buildings, and traffic management have special properties that traditional computing applications do not possess, such as context-awareness, massive decentralisation, autonomous behaviour, adaptivity, proactivity, and innate collaboration. In this paper we argue that these require a new computational model and middleware that can reflect the autonomy and spontaneity of cooperative entities. The EU funded CORTEX project proposes the sentient object model to support the construction of such large-scale applications. We report on a flexible, run-time reconfigurable component based middleware that we have used to engineer the sentient object programming paradigm. We demonstrate the appropriateness of the novel computational model and validity of the middleware by constructing a proof of concept demonstrator based on the notion of autonomous cooperating vehicles.

A new class of applications can now be envisaged with the emergence of both mobile ad hoc computing and ubiquitous computing. Applications of such kind are characterised by being largely distributed and proactive, i.e. able to operate without human intervention. The anonymous and asynchronous paradigm, which is advocated by event models, has shown to be well-suited for this kind of applications. However, current real-time event-oriented middleware technologies do not provide a complete solution for the requirements of mobile ad hoc environments. In this paper, we present the research carried out on both a resource and a QoS management framework to achieve real-time support for an event system operating in mobile ad hoc environments. The framework makes use of both reflection and component technology. The implementation of our resource system is developed in OpenCOM, which is a lightweight, efficient and reflective model based on Microsoft's COM.

Established middleware platforms such as CORBA and DCOM are not flexible enough to meet the needs of emerging distributed applications. This article discusses the architecture of Open ORB 2, a middleware platform based on reflection and component technology. Middleware has emerged as an important architectural component in modern distributed systems largely because it offers a high-level, platform-independent programming model that helps mask distribution problems. Examples of key middleware platforms include DCE, CORBA, DCOM, .NET, and the Java-based series of technologies, including RMI, Jini, and EJBs (for more information on these platforms, see the Middleware Platforms sidebar). Traditionally, developers have deployed such platforms in areas such as banking and finance to overcome heterogeneity and support the integration of legacy systems. More recently, however, developers have applied middleware technologies in a wider range of areas, including safety-critical, embedded, and real-time systems. It is now becoming apparent that middleware technologies cannot respond to such diverse requirements or technical challenges because of the limitations of the black-box philosophy maintained by developers of most existing middleware platforms. In particular, existing middleware platforms offer fixed services to their users; it is typically impossible to view or alter the implementation of these services. Inevitably, the architecture of this platform then represents a compromise design that features, for example, general-purpose protocols and associated management strategies. It is not possible to specialize platforms to meet the needs of more specific target domains. Other researchers in the field have also recognized these problems.1,2 Middleware designers are aware of these problems and have responded with several initiatives. The Object Management Group, focusing on CORBA, introduced a series of platform specifications that includes real-time CORBA and Minimal CORBA