Raft/Paxos and other consensus algorithms

Paxos and Raft are two algorithms for getting one answer from a group of unreliable processors. Some of the more popular use-cases for such algorithms are leader election, distributed locking, distributed log replication and so on.

Paxos was originally presented by Leslie Lamport in a very entertaining paper (that was rejected for publication many times). However, generalized Paxos is considered extremely hard to implement.

Raft was born as a easy to understand consensus algorithm and had several implementations to its credit.

In this session, I am planning to go over the problem of distributed log replication, walk through Paxos and its derivatives and then go through Raft. We can take a quick shot at implementing it, if time permits.