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 abstract the intricacies of a heterogeneous sup-porting environment (e.g., intrinsic characteristics of specific communication models) away from the application logic. These applications will be characterized by the increasing ubiquity of inter-actions between many possibly heterogeneous artifacts and services. This paper presents the Plug/Synapse abstraction, which provides a conceptual model for building ubiquitous computing applications in a high-level programming manner. GAS-OS is the software layer that implements the Plug/Synapse model and the concepts encapsulated in GAS, a generic architectural style, which can be used to describe everyday environments populated with computational artifacts. The paper examines also the design and architecture of GAS-OS, which is the minimum set of modules and functionalities that every device must afford, in order to be a ubiquitous computing artifact and participate in artifact collections