Analysis of Two Types Deniable Authentication Protocols

Deniability enables protocol participants to deny their involvement after they have taken part in a particular protocol run. In this paper, we present the security analysis of a class of interactive deniable authentication protocols and a noninteractive one. For interactive protocols, we focus on a serial of pairings based protocols proposed by Chou et al and repaired by Lim et al. We point out that their repaired protocols are still not secure under Key Compromise Impersonation (KCI) attack and give it an improvement. For noninteractive protocols, we point out that most current noninteractive deniable authentication protocols are not secure under KCI attack.