Abstract or Summary:
R. M. Needham mentioned a Personal Identification Number (PIN) management scheme for Automatic Teller Machine (ATM) transactions which provides enhanced privacy and the responsibility separation. This scheme was described as a rough example which supports his idea on security research under the changing computing environment. Though it shows a new approach to the role separation between a client and a server for PIN management, it needs some modification for application. A modified scheme for Needham’s one is suggested in this paper. Based on this modified scheme, we present a password management scheme for the UNIX systems with enhanced privacy and separated responsibility. Without serious modification of existing procedures and functions, this scheme provides higher privacy and security than that in the conventional UNIX password management scheme.