Upgrading the S-NCI Key Establishment Protocol Scheme to be Secure and Applicable

There are currently a number of key establishment protocols that have been developed with server based as trusted third parties. However, there are still some attacks that may occur in the protocols are man-in-the-middle attack, replay attack, typing attack, and modification attack. Following this, S-NCI's key establishment protocol has been developed which claims to be immune to man-in-the-middle attacks, replay attacks, typing attacks, and modification attacks. However, the protocol has not been through formal analysis. Then, based on experiments that have been done in this study, S-NCI has not met the formal analysis criteria of Alive and Weakaggree. In addition, S-NCI also has not provided an applicable supporting procedure for the utilization of Key Translation Center that is realized until now no one has applied. The research method used in this research is a research library supported by experimenting formal analysis of protocols using Scyther Tool. This research has produced a procedure supporting the application of S-NCI protocol along with the result of modification of the protocol so that it can fulfill Alive and Weakagree criteria.