2013/12/20 by Birenjith Sasidharan, Sasidharan, Birenjith, Kaushik Senthoor +3
Computer Science · Mathematics · #FOS: Computer and information sciences #Information Theory (cs.IT) #cs.IT #math.IT
paper · pdf · doi:10.48550/arxiv.1312.6079
14 pages
arxiv created 2013/12/20 · arxiv updated 2013/12/23
In this paper we establish an improved outer bound on the storage-repair-bandwidth tradeoff of regenerating codes under exact repair. The result shows that in particular, it is not possible to construct exact-repair regenerating codes that asymptotically achieve the tradeoff that holds for functional repair. While this had been shown earlier by Tian for the special case of [n,k,d]=[4,3,3] the present result holds for general [n,k,d]. The new outer bound is obtained by building on the framework established earlier by Shah et al.