%0 Conference Paper
%B In the Proceedings of the International Conference on NETworked sYStems}
%D 2015
%T Efficient State-based CRDTs by Delta-Mutation
%A Paulo Sérgio Almeida
%A Ali Shoker
%A Carlos Baquero Moreno
%C Agadir, Morocco
%I Springer
%S NETYS'15
%V 9466
%X <p>CRDTs are distributed data types that make eventual consistency of a distributed object possible and non ad-hoc. Specifically, state-based CRDTs ensure convergence through disseminating the entire state, that may be large, and merging it to other replicas; whereas operation-based CRDTs disseminate operations (i.e., small states) assuming an exactly-once reliable dissemination layer. We introduce Delta State Conflict-Free Replicated Datatypes (δ-CRDT) that can achieve the best of both worlds: small messages with an incremental nature, as in operation-based CRDTs, disseminated over unreliable communication channels, as in traditional state-based CRDTs. This is achieved by defining δ-mutators to return a delta-state, typically with a much smaller size than the full state, that is joined to both: local and remote states. We introduce the δ-CRDT framework, and we explain it through establishing a correspondence to current state-based CRDTs. In addition, we present an anti-entropy algorithm that ensures causal consistency, and we introduce two δ-CRDT specifications of well-known replicated datatypes.</p>
%8 13 May
%> https://haslab.uminho.pt/sites/default/files/ashoker/files/deltacrdt.pdf