Fractal blackboard framework

A command-and-control application developed at IET has recently undergone a major architectural change to use a blackboard framework. As opposed to many blackboard-based applications, in which the blackboard model is used to model only the top level of the application, we developed a blackboard framework that is fractal-like: the blackboard paradigm serves as the abstraction for all levels, recursively. We have also achieved maximal separation among the different blackboard-based elements at the various levels. This implies having small disconnected components which are flexible and reusable, and which together form the application. In this paper, we present our fractal blackboard framework and discuss interesting issues related to its design and usage