An improved NSSK protocol and its security analysis based on logic approach

Authentication protocol is a very important kind of protocol in network environment, and formal analysis is the key method to guarantee its security properties. Needham-Schroeder Shared-Key (NSSK) protocol is considered as one of the earliest and very important authentication protocol. The paper proposed a new improved version of NSSK protocol by modifying message format and decreasing message flows, and it also analysed the security of the proposed protocol by utilizing the formal approach based on logic. The analysis results reveal that the proposed protocol achieves the expectative authentication goals.