(Password) Authenticated Key Establishment: From 2-Party to Group

Abstract. A protocol compiler is described, that transforms any provably secure authenticated 2-party key establishment into a provably secure authenticated group key establishment with 2 more rounds of communication. The compiler introduces neither idealizing assumptions nor high-entropy secrets, e. g., for signing. In particular, applying the compiler to a password-authenticated 2-party key establishment without random oracle assumption, yields a password-authenticated group key establishment without random oracle assumption. Our main technical tools are non-interactive and non-malleable commitment schemes that can be implemented in the common reference string (CRS) model.

• Type: Conference
• Year: 2007
• Where: TCC
• Authors: Michel Abdalla, Jens-Matthias Bohli, Maria Isabel Gonzalez Vasco, Rainer Steinwandt
• Keywords: 2-party Key Establishment, Cryptography, Group Key Establishment, Key Establishment, TCC 2007