An Improved Computer Notary System Protocols

Computer notary system is an arbitrator or a notary public in the digital signature system, the process of arbitration, whether the signature is A communication sent to U, or U data are issued to B, after two and a signature encrypted password handling, you can ensure the security of communications. However, there is a signature of the arbitration serious problem: an intermediary can be replaced counterfeit information, and the agreement can not resist the replay attack. Article in the back of improved vulnerability of the agreement, and analyzes a new protocol security.