An Improved Outer Bound on the Storage-Repair-Bandwidth Tradeoff of Exact-Repair Regenerating Codes


Autoria(s): Sasidharan, Birenjith; Senthoor, Kaushik; Kumar, Vijay P
Data(s)

2014

Resumo

While the tradeoff between the amount of data stored and the repair bandwidth of an (n, k, d) regenerating code has been characterized under functional repair (FR), the case of exact repair (ER) remains unresolved. It is known that there do not exist ER codes which lie on the FR tradeoff at most of the points. The question as to whether one can asymptotically approach the FR tradeoff was settled recently by Tian who showed that in the (4, 3, 3) case, the ER region is bounded away from the FR region. The FR tradeoff serves as a trivial outer bound on the ER tradeoff. In this paper, we extend Tian's results by establishing an improved outer bound on the ER tradeoff which shows that the ER region is bounded away from the FR region, for any (n; k; d). Our approach is analytical and builds upon the framework introduced earlier by Shah et. al. Interestingly, a recently-constructed, layered regenerating code is shown to achieve a point on this outer bound for the (5, 4, 4) case. This represents the first-known instance of an optimal ER code that does not correspond to a point on the FR tradeoff.

Formato

application/pdf

Identificador

http://eprints.iisc.ernet.in/51012/1/iee_sym_inf_the_2430_2014.pdf

Sasidharan, Birenjith and Senthoor, Kaushik and Kumar, Vijay P (2014) An Improved Outer Bound on the Storage-Repair-Bandwidth Tradeoff of Exact-Repair Regenerating Codes. In: IEEE International Symposium on Information Theory (ISIT), JUN 29-JUL 04, 2014, 2014 IEEE INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY (ISIT), pp. 2430-2434.

Publicador

IEEE

Relação

https://eprints.iisc.ernet.in/secure/51012/1/iee_sym_inf_the_2430_2014.pdf

http://eprints.iisc.ernet.in/51012/

Palavras-Chave #Electrical Communication Engineering
Tipo

Conference Proceedings

NonPeerReviewed