Enhancing Dependability through Quantum Entanglement In a Real-Time Distributed System

Alice and Bob play beach volleyball as teammates. When the opponent starts to serve, they both run toward the ball and show their intentions by shouting "It\´s mine". However, sometimes they collide with each other and sometimes neither of them attempts to receive the ball. In both cases they will blame each other for having made the same decisions. This can be formulated as a dependability problem as follows. Two processors jointly provide a real-time service which can be completed by exactly one processor. Assuming each processor is allowed to announce only one-bit information to decide which one to process the job, inevitably some of the jobs will get lost if only classical resources are used. In this paper, we show if these two processors share quantum entanglement, not only the system dependability can be enhanced; the faulty processor can also be identified.