Encyclopedia of Big Data Technologies

Living Edition
| Editors: Sherif Sakr, Albert Zomaya

Conflict-Free Replicated Data Types CRDTs

  • Nuno PreguiçaEmail author
  • Carlos Baquero
  • Marc Shapiro
Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-63962-8_185-1


A conflict-free replicated data type (CRDT) is an abstract data type, with a well-defined interface, designed to be replicated at multiple processes and exhibiting the following properties: (i) any replica can be modified without coordinating with other replicas and (ii) when any two replicas have received the same set of updates, they reach the same state, deterministically, by adopting mathematically sound rules to guarantee state convergence.


Internet-scale distributed systems often replicate data at multiple geographic locations to provide low latency and high availability, despite outages and network failures. To this end, these systems must accept updates at any replica and propagate these updates asynchronously to the other replicas. This approach allows replicas to temporarily diverge and requires a mechanism for merging concurrent updates into a common state. CRDTs provide a principled approach to address this issue.

As any abstract data type, a CRDT...

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This work was partially supported by NOVA LINCS (UID/CEC/04516/2013), EU H2020 LightKone project (732505), and SMILES line in project TEC4Growth (NORTE-01-0145-FEDER-000020).


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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.NOVA LINCS & DI, FCT, Universidade NOVA de LisboaCaparicaPortugal
  2. 2.HASLab/INESC TEC & Universidade do MinhoBragaPortugal
  3. 3.Sorbonne Université, LIP6 & INRIAParisFrance

Section editors and affiliations

  • Mohammad Sadoghi

There are no affiliations available