In this dissertation, we discuss the identity authentication and the methods of it. We analyses the different kinds of password authentication schemes. Two new schemes which are based on the polynomial password authentication and a dynamic password authentication which is based on the Chinese remainder theorem and RSA public-key cryptography are represented. Meanwhile we prove the Chinese remainder theorem in the distributive lattice on which we design a safe communication scheme.The dissertation can be divided into five parts. The first chapter is an introduction to the background of information security, and we emphasize that the dissertation is mainly concerned with the new password authentications and the new safe communication scheme on the knowledge of algebra. The second chapter introduces the identity verification in the internet environment, such as necessity, methods, technology and other things of identity verification. The third chapter introduces some kinds of password authentications and makes some analysis. Then two new schemes which are based on the polynomial password authentication and a dynamic password authentication which is based on the Chinese remainder theorem and RSA public-key cryptography are represented. In the fourth chapter, we introduce the lattice, the ideal and prove the Chinese remainder theorem in the distributive lattice on which we design a safe communication scheme. In the fifth chapter, we make a summary and introduce the work to be done. |