Using Virtualization Technology for Fault-Tolerant Replication in LAN

We present an architecture and an algorithm for Byzantine fault-tolerant state machine replication. Our algorithm explores the advantages of virtualization to reliably detect and tolerate faulty replicas, allowing the transformation of Byzantine faults into omission faults. Our approach reduces the total number of physical replicas from 3f+1 to 2f+1. Our approach is based on the concept of twin virtual machines, where there are two virtual machines in each physical host, each one acting as a failure detector of its twin.