Fault Tolerance for Outputs and Clients
Explore techniques to provide fault tolerance for outputs and clients in replicated state machines. Understand how to handle failures in output devices and clients through replication, defensive programming, and careful output selection. Learn approaches to tolerate Byzantine and fail-stop failures, including client replication strategies and command scheduling, to improve system reliability.
We have already discussed how to make a group of state machines tolerant to faults. However, the output of the state machines goes to the output devices read by the voter devices. The output and voter devices can also fail. In this lesson, we will discuss how to deal with such failures.
Fault-tolerant outputs
If we use a single output device for an ensemble of replicas, the resulting system would not be
Outputting externally
A major proportion of applications of state machine replication requires outputting to a client, system, or node not part of the group of replicas. Suppose a system of replicated state machines has an output node that collects outputs from all replicas and sends the combined output to its destination. In that case, failure ...