Faults and Improvements of an Enhanced Remote User Authentication Scheme Using Smart Cards

TL;DR

This paper analyzes security flaws in an existing smart card-based remote user authentication scheme and proposes modifications to ensure its proper functioning and security.

Contribution

It identifies incomplete information issues in Awasthi-Lal's scheme and offers modifications to improve its security and operational correctness.

Findings

Awasthi-Lal's scheme has incomplete information issues.

Modified scheme enhances security and proper functioning.

Analysis reveals vulnerabilities in previous schemes.

Abstract

In 2000, Hwang and Li proposed a remote user authentication scheme using smart cards to solve the problems of Lamport scheme. Later, Chan- Chang, Shen- Lin- Hwang and then Chang-Hwang pointed out some attacks on Hwang – Li’s scheme. In 2003, Shen, Lin and Hwang also proposed a modified scheme to remove these attacks. In the same year, Leung-Cheng-Fong-Chan showed that modified scheme proposed by Shen-Lin-Hwang is still insecure. In 2004, Awasthi and Lal enhanced Shen-Lin-Hwang’s scheme to overcome its security pitfalls. This paper analyses that the user U/smart card does not provide complete information for the execution and proper running of the login phase of the Awasthi- Lal’s scheme. Furthermore, this paper also modifies the Awasthi- Lal’s scheme for the proper functioning.