Glossary

BASE

The relaxed alternative to ACID for high-availability distributed stores: Basically Available, Soft state, Eventually consistent.

1 min read·4 sections
Open the interactive version → diagrams, practice & more

Definition

The relaxed alternative to ACID for high-availability distributed stores: Basically Available, Soft state, Eventually consistent.

How it works

Instead of blocking to stay perfectly consistent, a BASE system always answers (Basically Available), lets replicas disagree for a while (Soft state), and converges later (Eventual consistency). This is the trade Dynamo-style stores (Cassandra, DynamoDB) make to stay up across regions. ACID vs BASE is really the CAP trade-off — strong consistency vs availability — in two acronyms.

Common questions

What is BASE?

The relaxed alternative to ACID for high-availability distributed stores: Basically Available, Soft state, Eventually consistent.

How does BASE work?

Instead of blocking to stay perfectly consistent, a BASE system always answers (Basically Available), lets replicas disagree for a while (Soft state), and converges later (Eventual consistency). This is the trade Dynamo-style stores (Cassandra, DynamoDB) make to stay up across…

What is BASE used for in system design?

Instead of blocking to stay perfectly consistent, a BASE system always answers (Basically Available), lets replicas disagree for a while (Soft state), and converges later (Eventual consistency). This is the trade Dynamo-style stores (Cassandra, DynamoDB) make to stay up across…

Part of Glossary on SystemLore — system design explained with 148 deep topics, interactive diagrams, and a build-it-yourself game. Browse the glossary and "X vs Y" comparisons, or build this one →