Safeguarding Cryptographic Keys

URL: https://ieeexplore.ieee.org/document/4356614 Authors: G.R. Blakley

Abstract

Demonstrates that cryptographic keys can be safeguarded by distributing partial information to $n$ holders such that any $t$ of them can reconstruct the key, while any $t-1$ of them have absolutely no information about it. The construction uses hyperplanes in a $t$-dimensional space over a finite field: the secret is a point in the space, and each share defines a hyperplane passing through the secret. The $t$ hyperplanes uniquely determine the intersection point. This work appeared simultaneously and independently with Shamir’s construction.