Secret Sharing in User Hierarchy

Secret sharing in user hierarchy represents a challenging area for research. A lot of research work has already been done in this direction. This book presents a novel approach to share a secret among a hierarchy of users while overcoming the limitations of the already existing mechanisms. Traditional (k + 1; n)-threshold secret sharing, 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. Here we 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. At present, a number of efficient schemes exist for sharing a secret into a group of users who are arranged into a hierarchy. Incidentally, all existing schemes have been developed considering non-overlapping hierarchies. This book presents a generalization of the existing hierarchical secret sharing schemes, which is applicable to an overlapping or tangled user hierarchy.

received B.Tech and M.Tech degrees in Information Technology from West Bengal University of Technology (2008) and IIT Kharagpur (2010), respectively. Currently she is a Ph.D. scholar in the Department of Computer Science and Engineering at IIT Kharagpur. Her research interests are Cryptography, Digital Forensics, Multimedia Security.