New Results on Multilevel Diversity Coding with Secure Regeneration

TL;DR

This paper extends the understanding of secure multilevel diversity coding with regeneration by showing the MBR point remains unchanged under a broader eavesdropper access model, enhancing security insights.

Contribution

It demonstrates that the MBR point is invariant even when the eavesdropper accesses different types of compromised nodes, generalizing previous results.

Findings

MBR point remains the same under new eavesdropper model

Security tradeoff region is robust to different compromised node types

Extends prior characterization of the tradeoff region

Abstract

The problem of multilevel diversity coding with secure regeneration is revisited. Under the assumption that the eavesdropper can access the repair data for all compromised storage nodes, Shao el al. provided a precise characterization of the minimum-bandwidth-regeneration (MBR) point of the achievable normalized storage-capacity repair-bandwidth tradeoff region. In this paper, it is shown that the MBR point of the achievable normalized storage-capacity repair-bandwidth tradeoff region remains the same even if we assume that the eavesdropper can access the repair data for some compromised storage nodes (type 2 compromised nodes) but only the data contents of the remaining compromised nodes (type 1 compromised nodes), as long as the number of type 1 compromised nodes is no greater than that of type 2 compromised nodes.