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Construction of Binary Locally Repairable Codes with Nonuniform Locality and Availability Using Combinatorial
1School of Information Management, Shanghai Lixin University of Accounting and Finance, Shanghai 201209, China.
Entropy (Basel, Switzerland)
|March 28, 2025
Summary
This study introduces new binary locally repairable codes (LRCs) using design theory. These codes offer improved performance and address open problems in coding theory.
Area of Science:
- Coding Theory
- Combinatorial Design Theory
Background:
- Locally Repairable Codes (LRCs) are crucial for distributed storage systems, enabling efficient data recovery.
- Existing constructions often lack flexibility in locality or availability, and binary implementations are preferred for practical use.
Purpose of the Study:
- To generalize the construction of LRCs using Pairwise Balanced Designs (PBDs) and Balanced Incomplete Block Designs (BIBDs).
- To develop binary LRCs with nonuniform locality or availability, achieving optimal or near-optimal performance.
- To address open problems, such as constructions where r does not divide k.
Main Methods:
- Leveraging PBDs and BIBDs for code construction.
- Prioritizing binary code implementations.
- Analyzing code rate, minimum distance, and repair efficiency.
Main Results:
- Proposed distance-optimal LRCs with nonuniform localities and message-symbol (r,t)-availability.
- Achieved optimal minimum distance under known bounds for binary codes.
- Demonstrated higher code rates compared to existing constructions.
- Showcased constructions where r does not divide k.
Conclusions:
- The proposed PBD and BIBD-based constructions provide a powerful framework for generalized LRCs.
- These binary codes offer superior performance and broader applicability, outperforming prior works.
- The study advances the field of coding theory with practical and efficient code designs.
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