Description
A code with \((r,\delta)\) locality is a code that encodes each codeword coordinate into an \([r+\delta-1,r,\delta]\) MDS code [1; Sec. 31.3.4.5]. In other words, given a codeword \(c\) and coordinate \(c_i\), there exists a coordinate set \(S_i\) of size \(\leq r+\delta-1\) such that the restriction \(C_{|S_i}\) of the code to that set is a code with minimum distance \(\delta\).
Protection
There is a generalized Singleton minimum distance bound [2], \begin{align} d\leq n-k+1-(\left\lceil k/r\right\rceil -1)(\delta-1)~, \tag*{(1)}\end{align} with codes saturating this bound being optimal codes with locality. The \(\delta=2\) case recovers optimal LRCs.
Parent
Children
- Locally recoverable code (LRC) — An LRC of locality \(r\) is a code with \((r,2)\) locality [1; Sec. 31.3.4.5].
- Maximally recoverable (MR) code
References
- [1]
- V. Ramkumar, M. Vajha, S. B. Balaji, M. Nikhil Krishnan, B. Sasidharan, P. Vijay Kumar, "Codes for Distributed Storage." Concise Encyclopedia of Coding Theory (Chapman and Hall/CRC, 2021) DOI
- [2]
- N. Prakash, G. M. Kamath, V. Lalitha, and P. V. Kumar, “Optimal Linear Codes with a Local-Error-Correction Property”, (2012) arXiv:1202.2414
Page edit log
- Victor V. Albert (2024-08-15) — most recent
Cite as:
“Code with locality”, The Error Correction Zoo (V. V. Albert & P. Faist, eds.), 2024. https://errorcorrectionzoo.org/c/code_with_locality