A family of multi-party authentication protocols

Abstract

We introduce a family of multi-party authentication protocols and discuss six novel protocols, which are members of this family. The first three generalize the well-known Needham-Schroeder-Lowe public-key protocol, the Needham-Schroeder private-key protocol, and the Bilateral Key Exchange protocol. The protocols satisfy injective synchronisation, which is a strong authentication property, and establish agreement over the nonces. These protocols make use of delegated authentication to keep the protocols small and efficient. For each of these protocols we define a strengthened version that does not rely on delegated authentication. All instantiations of the protocol family consist of 2p - 1 messages for p parties, which we show to be the minimal number of messages required to achieve the desired security properties in the presence of a Dolev-Yao style intruder with compromised agents