Leaderless replication.

also: leaderless · Dynamo-style replication · Dynamo-style · read repair

No leader: clients write to and read from several replicas directly, and quorums decide when a write or read counts.

the two-minute refresher

Writes go to N replicas; success once W acknowledge. Reads ask R replicas.
No failover step: any replica can take writes.
Clients must reconcile differing answers (read repair, version vectors).
Used by Dynamo-style stores such as Cassandra and Riak.
Read repair: when a quorum read sees different versions, the newest is written back to the stale replicas.

also: leaderless · Dynamo-style replication · Dynamo-style · read repair

No leader: clients write to and read from several replicas directly, and quorums decide when a write or read counts.

Writes go to N replicas; success once W acknowledge. Reads ask R replicas.
No failover step: any replica can take writes.
Clients must reconcile differing answers (read repair, version vectors).
Used by Dynamo-style stores such as Cassandra and Riak.
Read repair: when a quorum read sees different versions, the newest is written back to the stale replicas.