Formal Analysis and Verification of an Improved NSSK Protocol

Authentication protocols are the basis of network security.Needham-Schroeder Shared-Key(NSSK) protocol is considered as one of the earliest and classical authentication protocol.This paper introduces NSSK protocol,analyzes its security,and proposes an improved NSSK protocol.It is also modeled and verified by the framework of CSP and its model-checking tool FDR.The analysis results show that the proposed protocol can achieve the expectative authentication goals and the purpose of ensuring network security.