Saturday, June 23, 2018

Byzantine networks and the Byzantine Generals Problem

In some applications, networks and computer systems must be safe. Typically what we do is to use redundancy to protect against failures. If one component fails, another one takes over. As the tolerance for failure decreases, the cost and complexity of some of these systems increase. Byzantine networks study what happens when we have very little tolerance for failure. In fact, they consider what happens when one component does not just fail, but that component is malicious and tries to make the whole system fail.

The Byzantine Generals are a metaphor for a distributed network. In this metaphor the Generals are each computers networked together, each giving orders to their connected components. What happens when one General is 'malicious'. I.e. it fails in a way that it tries to take down other generals? What protocol should the generals adhere to so they don't follow a malicious generals? So the rest of the system operates normally.

Other than Byzantine networks there are other, less stringent architectures to protect against failures. These other solutions, such as redundancy and voting, relax the constraint of failure in various ways.

Following is a Link for a proposal to identify malicious players in Byzantine Network. This proposal assumes the network is a modern TCP/IP network, so 'omission' faults are identified by the underlying network. Click here to read the research proposal..