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Optimal Exact-Regenerating Codes for Distributed Storage at the MSR and MBR Points via a Product-Matrix Construction
In this paper, we present optimal, explicit constructions of (a) Minimum Bandwidth Regenerating (MBR) codes for all values of [n, k, d] and (b) Minimum Storage Regenerating codes that allow the number n of nodes in the network, to be chosen independent of the other parameters. Expand
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A Solution to the Network Challenges of Data Recovery in Erasure-coded Distributed Storage Systems: A Study on the Facebook Warehouse Cluster
We present a new storage code using our recently proposed "Piggybacking" framework, that reduces the network and disk usage during recovery by 30% in theory, while also being storage optimal and supporting arbitrary design parameters. Expand
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Information-Theoretically Secure Regenerating Codes for Distributed Storage
We consider a threat model where an eavesdropper may gain access to data stored in a subset of the storage nodes, and possibly also, to the data downloaded during repair of some nodes. Expand
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Interference Alignment in Regenerating Codes for Distributed Storage: Necessity and Code Constructions
We present the first explicit constructions of regenerating codes that achieve the cut-set bound on the repair bandwidth for the exact repair of systematic nodes. Expand
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Exact Regenerating Codes for Distributed Storage
A scheme of Exact Regenerating Codes is introduced, which are regenerating codes with an additional property of regenerating back the same node upon failure. Expand
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Explicit construction of optimal exact regenerating codes for distributed storage
We introduce Exact Regenerating Codes, which are regenerating codes possessing the additional property of being able to duplicate the data stored at a failed node. Expand
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A "hitchhiker's" guide to fast and efficient data reconstruction in erasure-coded data centers
Hitchhiker is a new erasure-coded storage system that reduces both network traffic and disk IO by around 25% to 45% during reconstruction of missing or otherwise unavailable data, with no additional storage, the same fault tolerance, and arbitrary flexibility in the choice of parameters, as compared to RS-based systems. Expand
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One extra bit of download ensures perfectly private information retrieval
We establish the capacity of private information retrieval (PIR) in erasure-coded systems by establishing its capacity and designing explicit codes and algorithms. Expand
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Double or Nothing: Multiplicative Incentive Mechanisms for Crowdsourcing
We propose a simple payment mechanism to incentivize workers to answer only the questions that they are sure of and skip the rest. Expand
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Having Your Cake and Eating It Too: Jointly Optimal Erasure Codes for I/O, Storage, and Network-bandwidth
Erasure codes, such as Reed-Solomon (RS) codes, are increasingly being deployed as an alternative to data-replication in distributed storage systems. Expand
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