Summary: Dynamo

Summary

Dynamo is a highly available key-value store that Amazon built for its own internal services. It shows how a business requirement can shape a system design: Amazon chose higher availability over strong consistency, because that is what its business needed. The design also assumes that system and hardware failures happen, not that they might happen.

Dynamo is a peer-to-peer system, with no leader and no follower nodes. Every node is equal, with the same roles and responsibilities. That symmetry is also what removes any single point of failure.