Research On Zero-Knowledge Proof And Digital Signature

Authentication systems play an important role in information security which is an effective method to prevent an adversary from tempering with > deleting and replaying the message and insure authenticity and integrality of the message . The key technologies of which are hash function zero knowledge proof and digital signature. In this paper these three technologies are researched in detail. The main results are the followings:1. The use of authentication code (hash function) is generalized and the classification of hash functions^ the attack methods and some open issues are introduced.2. The zero-knowledge proof scheme processing RSA digital signature is proposed which presents a new method to prevent RSA digital signature from spreading arbitrarily, in which signer doesn't need to give the signature of a message directly but provide a zero-knowledge proof to the digital signature of this message. The scheme is the improvementof confirmer digital signature. Also it is simpler and doesn't require the participation of the confirmer. The scheme is widely used to protect the copyright of information product.3. A digital signature scheme with multiple functions in special environment is proposed which is called forward-secure and confirmer digital signature scheme based on zero knowledge proof. It not only provides so-called forward-security i. e. an attacker can not forge the digital signatures related to past time period even if the secret key in current time period is exposed and it is useful to lessen the loss because of exposition, but also bases on zero-Knowledge proof protocol i.e. without exposing anything related to the signature. A part i.e. trusted third party called confirmer is introduced who should finish validating or denying a signature. Meanwhile, a confirmer is able to transfer a confirmer signature into a general signature that can be verified by anyone if he or she can obtain it. A confirmer doesn't take part in signing. The scheme is forward secure at random oracle model and can be used to sign fair digital contract.4. How to put extensible markup language into digital signature is also examined. The general method of building and verifying XML signature is proposed. XML signature takes XML as formulation to define signature, the properties of which is that is signed not on the entire document but on XML structure tree. Source document of multi-type can be signed in secure E-business. Different persons can sign different parts at different time. In conclusion, it is more flexible.