Résumé
Software dedicated to ubiquitous environments has to deal with the multiplicity of devices and users. It also has to adapt to frequent changes in its environment. Users can easily access and trigger services provided by different devices but also need to implement complex scenarios, i.e., structured compositions of multiple service. State-of-the-art frameworks do not fully meet the expectation we identified. This is why, we designed the SaS (Scenarios As Services) ubiquitous software: a platform for ubiquitous systems that provides a SDL (Scenario Description Language) to support the creation of tailored user-centric scenarios. Our previous work on the subject did not tackle all distribution and concurrency concerns. In this paper, we present SaS's new features. Using the improved SDL, a user can now describe scenarios that combine services even if all of them are not currently available and will never be at the same time. Moreover, different scenario sharing mechanisms coupled with an access right policy are now included in SaS. SaS is currently implemented in a prototype on top of OSGi.