A Novel Rekeying Message Authentication Procedure Based on Winternitz OTS and Reconfigurable Hardware Architectures

Secure multicast demands an efficient rekeying solution to update and to distribute the group key on every change in the group membership. This paper treats the authentication of rekeying messages with three new contributions. First, to accelerate group rekeying the Winternitz one-time signature scheme is applied to authenticate rekeying messages. Second, a hardware realization of Winternitz-OTS is presented and evaluated regarding resource usage and performance. Third, this hardware prototype is integrated into a rekeying processor. Due to this integration the rekeying processor establishes rekeying messages under a performance enhancement of more than one order of magnitude.