Big Data Dictionary
CAP Theorem
The CAP theorem describes the existence of direct tradeo-off s between consistency and availability as well as consistency and latency goals in distributed systems. For example, The CAP theorem shows that a distributed database system can only choose at most two out of three properties: Consistency, Availability and tolerance to Partitions (the system still functions when distributed replicas cannot talk to each other). Hence, according to the CAP theorem, systems can be classi ed based on their support of the properties of the CAP theorem into three categories:
- CA systems: Consistent and highly available, but not partition-tolerant.
- CP systems: Consistent and partition-tolerant, but not highly available.
- AP systems: Highly available and partition-tolerant, but not consistent.
