Quantum Advantage of Threshold Changeable Secret Sharing Scheme

TL;DR

This paper demonstrates a quantum approach to threshold changeable secret sharing that ensures old shares are effectively invalidated, providing a quantum advantage over classical methods in maintaining secret security.

Contribution

It introduces a quantum method to enforce threshold changes in secret sharing, preventing adversaries from reconstructing secrets using old shares.

Findings

Quantum TCSS guarantees old shares are invalidated.

Quantum approach enforces mandatory threshold change.

Quantum advantage over classical schemes in security.

Abstract

In TCSS (Threshold Changeable Secret Sharing) scheme, the threshold can be changed to deal with share leakage in the long term. But in classical TCSS, there is no guarantee that old shares are deleted even if the participated parties are honest. So, the changed threshold may not prevent an adversary from reconstructing the secret by the old shares and old threshold number of parties. We show how to tackle this problem quantum mechanically. I.e., quantum mechanically we can make the changed threshold mandatory. So, there is quantum advantage of quantum TCSS over classical TCSS.