Dependable system codesign using data flow models

The need to account for both spatial and temporal redundancy in dependable system design requires the use of abstractions that model both hardware and software. To answer this, the authors present a novel approach to designing dependable systems by using hardware/software codesign request-resource models. Out of this work, the authors aim to demonstrate how dependability analysis can be embedded into the design cycle, a currently difficult situation due to the difference in paradigms used to construct systems as opposed to analyzing them. A framework for dependable system design is presented to show how codesign models can be generated using rapid prototyping techniques. This framework is implemented in a design environment called ADEPT (ADvanced Environment Prototype Tool). Codesign models are built from a library of nodes that adhere to a data flow model of computation. The prototype codesign models can then be analyzed for their functional, performance, and dependable characteristics. An example system using a 3N code was modeled to demonstrate the utility of the framework in doing trade-off analysis during its design.