Information theoretical lower bounds for unconditionally secure group authentication

The single sender single receiver authentication model was extended by Desmedt and Frankel (1991) to the case where certain groups of persons are able to sign a message. The problem is further developed and discussed by Desmedt (1994). The unconditionally secure group authentication problem was formulated and investigated using the generalized vector space construction (van Dijk et al., 1995). We give information theoretic bounds on the security of a group authentication scheme and propose a construction based on the Shamir secret sharing scheme and maximum rank distance codes (MRD-codes)