Future networked embedded systems will be complex deployments deeply integrated in the environment that they monitor. They will have to react to both user and environmental events, and this may require modifying their structure to handle the changing situations. In a number of domains including industrial environments, this modification of the system structure will need to take place in real time. This is a hard problem that will require novel and paradigmatic solutions involving cross-domain knowledge to build a middleware for enabling real-time interaction between nodes allowing time-bounded reconfiguration. For supporting real-time, this middleware must be vertically architected in a modular way from the network and operating system levels up to the application software and the real-time policies for achieving time-bounded behavior. This paper presents a middleware that addresses these characteristics supporting timely reconfiguration in distributed real-time systems based on services. Experimental results are shown to validate the middleware in an actual small-scale video prototype.

This paper presents a model for quality-of-service (QoS)-aware service composition in distributed systems with real-time and fault-tolerance requirements. This model can be applied in application domains like, for example, remote monitoring, control and surveillance. Classic approaches to real-time systems do not provide the flexibility and fault-tolerance required in new emerging environments that need to combine a high degree of dynamism with temporal predictability. Our approach addresses these new challenges by combining concepts from the service oriented paradigm and distributed real-time systems. We propose a concrete system model based on a holistic time-triggered-based approach for design and configuration. Based on this model, we propose two algorithms for the composition of QoS-aware service-based applications with temporal requirements: an exhaustive algorithm that computes the optimal service combination in terms of a figure of merit, suitable for offline composition; and an improved algorithm based on heuristics and partial figures of merit, suitable for online composition. Experimental results show that the latter reduces dramatically the number of combinations explored with a minimal degradation in the quality of the solution, making it feasible for online execution in dynamic environments.

The design of embedded real-time systems requires skills from multiple specific disciplines, including, but not limited to, control, computer science, and electronics. This often involves experts from differing backgrounds, who do not recognize that they address similar, if not identical, issues from complementary angles. Design methodologies are lacking in rigor and discipline so that demonstrating correctness of an embedded design, if at all possible, is a very expensive proposition that may delay significantly the introduction of a critical product. While the economic importance of embedded systems is widely acknowledged, academia has not paid enough attention to the education of a community of high-quality embedded system designers, an obvious difficulty being the need of interdisciplinarity in a period where specialization has been the target of most education systems. This paper presents the reflections that took place in the European Network of Excellence Artist leading us to propose principles and structured contents for building curricula on embedded software and systems.