Date of Award


Publication Type

Master Thesis

Degree Name



Computer Science

First Advisor

Aggarwal, A. K.


Computer Science.




To address the challenges of user authentication in distributed systems, many protocols have been proposed. Among them is the Proactive Two-party Signatures Scheme (P2SS). P2SS has not so far been investigated in detail. Using P2SS, I have developed a system, called Proactive User-authentication in a Distributed Environment (PUDE) in which two parties (the client and server) use a 2-part signature algorithm, based on standard (one part) RSA algorithm. In this scheme the client and the server jointly produce the signatures. If the password of the user is compromised, the system can recover by changing the share of the private key and the password on the primary server only. To test PUDE, a basic multi-realm test-bed called the Secure Multi-realm System (SMS) has been designed. PUDE is able to bring out the usefulness of a proactive two-party signature scheme over different realms. Its security is based on the unacceptable high computational effort required for computing discrete logs. This is a widely-accepted basis of security for security protocols. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2003 .S53. Source: Masters Abstracts International, Volume: 42-03, page: 0973. Adviser: A. K. Aggarwal. Thesis (M.Sc.)--University of Windsor (Canada), 2003.