Secret Sharing and Proactive Renewal of Shares in Hierarchical Groups

Secret sharing in user hierarchy represents a challenging area for research. Although a lot of work has already been done in this direction, this paper presents a novel approach to share a secret among a hierarchy of users while overcoming the limitations of the already existing mechanisms. Our work is based on traditional (k + 1, n)-threshold secret sharing, which is secure as long as an adversary can compromise not more than k secret shares. But in real life it is often feasible for an adversary to obtain more than k shares over a long period of time. So, in our work we also present a way to overcome this vulnerability, while implementing our hierarchical secret sharing scheme. The use of Elliptic Curve Cryptography makes the computations easier and faster in our work. Keywords. Threshold secret sharing, User hierarchy, Proactive secret sharing, Elliptic curve cryptography.

• Type: Journal
• Year: 2010
• Where: CORR
• Authors: Ruchira Naskar, Indranil Sengupta
• Keywords: CORR 2010, Education, Secret Sharing, Sharing, User Hierarchy