A COMPILER THAT INCREASES THE FAULT TOLERANCE OF ASYNCHRONOUS PROTOCOLS

A compiler that increases the fault tolerance of certain asynchronous protocols is presented. Specifically, it transforms a source protocol that is resilient to crash faults into an object protocol that is resilient to Byzantine faults. The compiler simplifies the design of protocols for the Byzantine fault model because it allows the design process to be broken into two steps. The first step is to design a protocol for the crash fault model. The second step, which is completely mechanical, is to compile the protocol into one for the Byzantine fault model. The compiler is used to produce a asynchronous approximate agreement protocol that operates in the Byzantine fault model and improves in several respects on the performance of the asynchronous approximate agreement prototol of D. Dolev et al. (1986).