A Hierarchical Reparable Key Distrubution Protocol And Its Application In E-gov

The development of cryptography provides technical basis for modern information security technologies. The security of any cryptosystem depends on the security of the cryptographic keys used in the system. The security issue of keys in conventional cryptosystem mainly concerns with secrecy and anti-crackdown of the key material, while in public key system this issue mainly means the correctly banding between the public key and the owners identity. Since the both communication parties must share symmetric key, it is of most importance to keep the key secure in its distributing paths respectively up to both parties. In this dissertation, concepts and technologies of symmetric and asymmetric cryptography are discussed; the direction of cryptography is analyzed based on their status and use in modern information security fields. There are varies information security services, of which authentication is the concern of the thesis. The objectives, means and protocols of authentication are studied in detail. The idea, logic rules and methods of BAN logic, a famous authentication protocol analysis tool which is proposed by Burrows, Abadi and Needham, is studied and expanded in this paper. Key distribution technologies and protocols are discussed as well. The relations between authenticating and key distributing processes are investigated. The reparability of key distribution protocols is studied. And the essential reason for irreparability of several protocols is revealed, and a method to produce unrepeatable and unpredictable Session Marker is brought out to hurdle this defect. A new key distribution protocol is proposed out based on all researches upon. This protocol is verified by applying the expanded BAN logic, and its reparability is proved as well in the same chapter, and a hierarchical key distribution system model is given out and the corresponding expanded protocol, which we call Authentication Based Hierarchical Reparable Key Distribution Protocol, is proposed as well.Hierarchical architecture is common organization structure in the army, government and enterprise. Our hierarchical protocol proposed is applicable for these organizations. We take Personnel Administrations Departments in Sichuan Province as an example to demonstrate the deploying of our protocol.