see CAP Theorem
Brewer's Theorem is essentially another name for the CAP Theorem. The CAP Theorem, which stands for Consistency, Availability, and Partition Tolerance, states that it is impossible for a distributed data store to simultaneously provide more than two out of these three guarantees:
- Consistency: Every read receives the most recent write or an error.
- Availability: Every request receives a response, without guarantee that it contains the most recent write.
- Partition Tolerance: The system continues to operate despite an arbitrary number of messages being dropped (or delayed) by the network between nodes.
Eric Brewer conjectured this theorem in a 2000 keynote at the Symposium on Principles of Distributed Computing (PODC), and it was later proven by Seth Gilbert and Nancy Lynch of MIT. Hence, it is also known as Brewer's Theorem.