1 Password-Authenticated Constant-Round Group Key Establishment with a Common Reference String

Jens-Matthias Bohli, María Isabel González Vasco, González Vasco, Rainer Steinw

Published Jul 25, 2013• 27 citations

Abstract

Abstract. A provably secure password-authenticated protocol for group key establishment in the common reference string (CRS) model is presented. Our construction assumes the participating users to share a common password and combines projective hashing as introduced by Cramer and Shoup with a construction of Burmester and Desmedt. Our protocol is constant-round. Namely, it is a three-round protocol that can be seen as generalization of a two-party proposal of Gennaro and Lindell.

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