135 research outputs found
Update-Efficient Regenerating Codes with Minimum Per-Node Storage
Regenerating codes provide an efficient way to recover data at failed nodes
in distributed storage systems. It has been shown that regenerating codes can
be designed to minimize the per-node storage (called MSR) or minimize the
communication overhead for regeneration (called MBR). In this work, we propose
a new encoding scheme for [n,d] error- correcting MSR codes that generalizes
our earlier work on error-correcting regenerating codes. We show that by
choosing a suitable diagonal matrix, any generator matrix of the [n,{\alpha}]
Reed-Solomon (RS) code can be integrated into the encoding matrix. Hence, MSR
codes with the least update complexity can be found. An efficient decoding
scheme is also proposed that utilizes the [n,{\alpha}] RS code to perform data
reconstruction. The proposed decoding scheme has better error correction
capability and incurs the least number of node accesses when errors are
present.Comment: Submitted to IEEE ISIT 201
Error Resilience in Distributed Storage via Rank-Metric Codes
This paper presents a novel coding scheme for distributed storage systems
containing nodes with adversarial errors. The key challenge in such systems is
the propagation of erroneous data from a single corrupted node to the rest of
the system during a node repair process. This paper presents a concatenated
coding scheme which is based on two types of codes: maximum rank distance (MRD)
code as an outer code and optimal repair maximal distance separable (MDS) array
code as an inner code. Given this, two different types of adversarial errors
are considered: the first type considers an adversary that can replace the
content of an affected node only once; while the second attack-type considers
an adversary that can pollute data an unbounded number of times. This paper
proves that the proposed coding scheme attains a suitable upper bound on
resilience capacity for the first type of error. Further, the paper presents
mechanisms that combine this code with subspace signatures to achieve error
resilience for the second type of errors. Finally, the paper concludes by
presenting a construction based on MRD codes for optimal locally repairable
scalar codes that can tolerate adversarial errors
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