STRONG AND EVENTUAL CONSISTENCY IN NOSQL DATABASES
Access model to database for asynchronous eventual consistency (W = R = 1) case was developed in this paper. We obtained the estimate of probability that in process of the asynchronous updating N replicas at least one requirement will arrive to read from the unpatched replicas. It was developed an access model for in-sync state of strong consistency (W = R = N/2 + 1) case. By requirement to read the end of replicas updating (N/2 + 1) the estimate of the waiting time was obtained.
Keywords: NoSQL database, eventual consistency, strong consistency, Laplase-Stieltjes transformation, generating function, access probability, waiting time