Basically Available, Soft State, Eventual Consistency (BASE)

BASE may be explained in contrast to another design philosophy - Atomicity, Consistency, Isolation, Durability (ACID). The ACID model promotes consistency over availability, whereas BASE promotes availability over consistency.

Experts have noted that BASE requires a level of "failure," or lack of consistency, that makes a data operation run less effectively without overburdening users. An example is when a designer relaxes the consistency of a financial transactional database by allowing for lag time between a transaction and account updates. Allowing less constantly updated data gives developers the freedom to build other efficiencies into the overall system. In other words, elements like consistency and availability often are viewed as resource competitors, where adjusting one can impact another. In BASE, engineers embrace the idea that data has the flexibility to be "eventually" updated, resolved or made consistent, rather than instantly resolved.