CAP theorem: revision of its related consistency models
Fecha
2019Autor
Versión
Acceso abierto / Sarbide irekia
Tipo
Artículo / Artikulua
Versión
Versión aceptada / Onetsi den bertsioa
Impacto
|
10.1093/comjnl/bxy142
Resumen
The CAP theorem states that only two of these properties can be simultaneously guaranteed in
a distributed service: (i) consistency, (ii) availability, and (iii) network partition tolerance. This
theorem was stated and proved assuming that “consistency” refers to atomic consistency. However,
multiple consistency models exist and atomic consistency is located at the strongest edge of that
spec ...
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The CAP theorem states that only two of these properties can be simultaneously guaranteed in
a distributed service: (i) consistency, (ii) availability, and (iii) network partition tolerance. This
theorem was stated and proved assuming that “consistency” refers to atomic consistency. However,
multiple consistency models exist and atomic consistency is located at the strongest edge of that
spectrum.
Many distributed services deployed in cloud platforms should be highly available and scalable.
Network partitions may arise in those deployments and should be tolerated. One way of dealing
with CAP constraints consists in relaxing consistency. Therefore, it is interesting to explore the set
of consistency models not supported in an available and partition-tolerant service (CAP-constrained
models). Other weaker consistency models could be maintained when scalable services are deployed
in partitionable systems (CAP-free models). Three contributions arise: (1) multiple other CAPconstrained
models are identified, (2) a borderline between CAP-constrained and CAP-free models
is set, and (3) a hierarchy of consistency models depending on their strength and convergence is built. [--]
Materias
Inter-replica consistency,
CAP theorem,
Service availability,
Network partition,
Consistency model
Editor
Oxford University Press
Publicado en
The Computer Journal, Volume 62, Issue 6, June 2019, Pages 943–960
Departamento
Universidad Pública de Navarra. Departamento de Estadística, Informática y Matemáticas /
Nafarroako Unibertsitate Publikoa. Estatistika, Informatika eta Matematika Saila