Fault-tolerant Distributed Systems with Diagnostics Algorithms

To provide consistent actions in distributed systems with faulty nodes the Byzantine agreement protocol (algorithm) is widely used. In case of using message exchange scheme without authentication the Byzantine agreement algorithm leads to agreement if the number of nodes doesn’t exceed 1/3 of the total number. The proposed algorithms based on diagnostics procedures are used to reach an agreement in distributed models with 2n+ 2 nodes and fewer than k failed nodes. The hierarchical diagnostic procedures give the possibility to vary the complexity of hardware and software overhead according to required level of fault-tolerance.