On the Tradeoff Region of Secure Exact-Repair Regenerating Codes Conference Paper uri icon


  • 2017 IEEE. We consider the {n, k, d, l) secure exact-repair regenerating code problem, which generalizes the {n, k, d) exact-repair regenerating code problem with the additional constraint that the stored file needs to be kept information-theoretically secure against an eavesdropper, who can access the data transmitted to regenerate a total of l different failed nodes. For all known results on this problem, the achievable tradeoff regions between the normalized storage capacity and repair bandwidth have a single corner point, achieved by a scheme proposed by Shah, Rashmi and Kumar (the SRK point). Since the achievable tradeoff regions of the exact-repair regenerating code problem without any secrecy constraints are known to have multiple corner points in general, these existing results suggest a phase-change-like behavior, i.e., enforcing a secrecy constraint (l 1) immediately reduces the tradeoff region to one with a single corner point. In this work, we first show that when the secrecy parameter l is sufficiently large, the SRK point is indeed the only corner point of the tradeoff region. However, when is small, we show that the tradeoff region can in fact have multiple corner points. In particular, we establish a precise characterization of the tradeoff region for the (7, 6, 6,1) problem, which has exactly two corner points. Thus, a smooth transition, instead of a phase-change-type of transition, should be expected as the secrecy constraint is gradually strengthened.

name of conference

  • 2017 IEEE International Symposium on Information Theory (ISIT)

published proceedings


author list (cited authors)

  • Shao, S., Liu, T., Tian, C., & Shen, C.

citation count

  • 1

complete list of authors

  • Shao, Shuo||Liu, Tie||Tian, Chao||Shen, Cong

publication date

  • January 2017