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arXiv · 1502.04496

Don't Trust the Cloud, Verify: Integrity and Consistency for Cloud Object Stores

Marcus Brandenburger·Christian Cachin·Nikola Knežević
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Abstract

Cloud services have turned remote computation into a commodity and enable convenient online collaboration. However, they require that clients fully trust the service provider in terms of confidentiality, integrity, and availability. Towards reducing this dependency, this paper introduces a protocol for verification of integrity and consistency for cloud object storage (VICOS), which enables a group of mutually trusting clients to detect data-integrity and consistency violations for a cloud object-storage service. It aims at services where multiple clients cooperate on data stored remotely on a potentially misbehaving service. VICOS enforces the consistency notion of fork-linearizability, supports wait-free client semantics for most operations, and reduces the computation and communication overhead compared to previous protocols. VICOS is based in a generic way on any authenticated data structure. Moreover, its operations cover the hierarchical name space of a cloud object store, supporting a real-world interface and not only a simplistic abstraction. A prototype of VICOS that works with the key-value store interface of commodity cloud storage services has been implemented, and an evaluation demonstrates its advantage compared to existing systems.

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Marcus Brandenburger, Christian Cachin, Nikola Knežević. 2015-02-16. Don't Trust the Cloud, Verify: Integrity and Consistency for Cloud Object Stores. https://arxiv.org/abs/1502.04496

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