A Conceptual Model and the Supporting Middleware for Composing Ubiquitous Computing Applications

Given the resulting complexity of the ambient applications that one can form in the Ubiquitous or Pervasive Computing domain it is required to abstra ct the intrinsic characteristics of specific communica tion models away from the application logic. These applications will be characterized by the increasin g ubiquity of interactions between many possibly heterogeneous artifacts and services. This paper presents the Plug/Synapse abstraction, which provid es a conceptual model for building ubiquitous computing applications in a high-level programming manner. GA SOS is the software layer that implements the Plug/Synapse model and the concepts encapsulated in GAS, a generic architectural style, which can be us ed to describe everyday environments populated with computational artifacts. The paper focuses on the d esign and architecture of GAS-OS, which is the minimum se t of modules and functionalities that every device mu st have, in order to be a ubiquitous computing artifac and participate in artifact collections.