System Support and Dependable Adaptation in Small Real-Time Embedded Systems

Last years have seen a widespread use of small electronic devices with processing and communications capabilities. Based on these pervasive devices new classes of applications are developed in several different domains. Application complexity is also growing and they present ever increasing requirements in what concerns dependability and real-time characteristics. Despite the technological evolution in terms of processing power and chip integration, many of these devices still show limitations regarding available resources. The need to obtain devices that are small in size, with low power consumption, and low cost, implies that resources such as processing power and memory capacity can not grow in an uncontrolled way. In this scenario, not being always possible, at a given moment, to provide the desired quality-of-service (QoS), it is necessary and convenient to be able to choose between several different QoS as a way to achieve a better adaptation to the evolution of the surrounding environment. In this paper we address the issue of providing support (containing or not an operating system) as a way to help in the development of applications, running in small embedded systems, and able to adapt in a dependable way the QoS that they offer.