Verifiable Computing in Avionics for Assuring Computer-Integrity without Replication

Safety-critical digital systems such as Fly-by-wire control have demanding integrity and availability requirements which significantly exceed the occurrence rates of random hardware faults observed in digital computers. As a result, system designers need to employ reliable fault detection and mitigation techniques. Until now, the only method to achieve sufficiently reliable fault detection for systems that can cause hazardous or catastrophic events, is to replicate computer lanes and detect faults by comparing outputs. However, this comes with a large overhead in development cost, computing resources and additional requirements towards the application. We propose to apply a novel cryptographic technique to reliably detect faults and thereby assure integrity of avionics computers: Succinct Non-Interactive Arguments of Knowledge allow components to quickly verify computations without repeating the computation. We present a novel concept for building high-integrity avionics systems and set up a laboratory demonstrator for a simplified pitch control system. Our major results include the successful demonstration of the first self-proving and self-verifying cyber-physical system in a laboratory environment.