On a Simple Characterization of Secure Exact-repair Regenerating Codes
Fangwei Ye, Shiqiu Liu, Kenneth W. Shum, Raymond W. Yeung · 2018
The problem of exact-repair regenerating codes against eavesdropping attack is studied. The eavesdropping model we consider is that the eavesdropper has the capability to observe the data involved in the repair of a subset of l nodes. Under this security constraint, it has been shown that the optimal tradeoff curve has a single corner point for some (n, k, d, l). The focus of this paper is on finding parameters (n, k, d, l) whose associated tradeoff curve has this behavior. For k=d=n-1, we prove that the tradeoff curve has a single corner point if and only if l ≥ [[1/4](d-1)]. Previously, it was known that the tradeoff curve has a single corner point if l ≥ [(√d-1)2].