No abstract

No abstract

No abstract

No abstract

This paper proposes two ID-based password authentication schemes, which does not require a dictionary of passwords or verification tables, with smart card and fingerprint. In these schemes, users can change their passwords freely. For a network without synchronization clocks, the proposed nonce-based authentication scheme can withstand message replay attacks . The proposed two schemes require a system to authenticate each user by each user's knowledge, possession, and biometrics, and this feature makes our schemes more reliable .The rapid progress of networks facilitates more and more computers connecting together to exchange great information and share system resources . Security is then an important issue for computer networks. Entity authentication is one of the most important security services . It is, necessary to verify the identities ofthe communication parties when they start a connection [1] .The concept of ID-based cryptosystems was first proposed by Shamir [2] . The ID-based cryptosystems have the following advantages: neither secret nor public keys need be exchanged, the public key directory table is not needed, and the assistance of a trusted third parry is not needed. The secret key corresponding to an ID is fixed and cannot be changed in Shamir's IDbased scheme . Therefore, a user with an assigned ID cannot choose his password by himself.Actually, a user's password is generated by the password generation center, rather than by the user himself. However, users are used to choosing their own passwords . This approach is against ofthe users' habits .Based on ElGama1's signature in [3] and Shamir's ID-based schemes, the concept of 32