Redesigning group key exchange protocol based on bilinear pairing suitable for various environments

Abstract

Group key exchange (GKE) allows a group of n parties to share a common secret key over insecure channels. Since key management is important, NIST is now looking for a standard. The goal of this paper is to redesign GKE using bilinear pairings, proposed by Desmedt and Lange, from the point of view of arrangement of parties. The arrangement of parties is called a party tree in this paper. Actually, we are able to redesign the party tree, to reduce the computational and communicational complexity compared with the previous scheme, when GKE is executed among a small group of parties. We also redesign the general party tree for a large number of parties, in which each party is in a different environment such as having large or limited computational resources, electrical power, etc. © 2011 Springer-Verlag.