Compositional Verification of a Communication Protocol for a Remotely Operated Vehicle

Abstract

We present the specification and verification, in PVS, of a protocol intended to facilitate communication in an experimental remotely operated vehicle used by NASA researchers. The protocol is defined as a stack-layered composition of simpler protocols. It can be seen as the vertical composition of protocol layers, where each layer performs input and output message processing, and the horizontal composition of different processes concurrently inhabiting the same layer, where each process satisfies a distinct requirement. We formally prove that the protocol components satisfy certain delivery guarantees. Then, we demonstrate compositional techniques that allow us to prove that these guarantees also hold in the composed system. Although the protocol itself is not novel, the methodology employed in its verification extends existing techniques by automating the tedious and usually cumbersome part of the proof, thereby making the iterative design process of protocols feasible.

This work was supported by the National Aeronautics and Space Administration under NASA Cooperative Agreement NNX08AE37A awarded to the National Institute of Aerospace. This work was done while the second author was resident at the National Institute of Aerospace. Authors are in alphabetical order.