Yes, there is the notion of what CAP requires, but we cannot cling to the strict definitions of these papers. They must be translated in to lay persons terms.

Yes, there is the notion of what CAP requires, but we cannot cling to the strict definitions of these papers. They must be translated in to lay persons terms. If you don't, how else can you communicate with your stakeholders? How can you communicate with your users? Personally I refuse the notion that this is out of scope of our jobs. Think of the ability and power of a so-called 'renaissance person' - can do anything. > The definition of consistency and availability doesn't allow you to "fail over". Completely ignoring availability, there are two cases of failover: one where the system still appears to be consistent (using one of the strong consistency models described here), and one where the system becomes eventually consistent. The various proofs (such as Gilbert and Lynch's CAP proof) imply that you can't "fail over" and keep consistency in the case where some nodes are uncontactable. The definition of "some nodes" depends on the exact proof, but there is no way to fail over into a minority partition and keep consistency. It's not possible. Minority partition - maybe you could restate this paragraph in terms of discoveries such as paxos? Does paxos not allow progress and data retrieval during some failure scenarios? Yes, realistically once enough nodes are lost, things grind to a halt. But this is how dynamo works as well. Once the # of nodes available declines below the R or W factor, the algorithm stops making progress.