Research And Implementation Of Electronic Seal System Based On CA

Electronic Seal System is used to make sure the document flow to be real effective and not be tampered in the open network environment. The system is based on cryptography, PKI(public key infrastructure), watermarking technology, database technology, component technology, it realizes the electronic document seal, document verification, authority control, certificate management and other functions.Electronic Seal System and CA(Certificate Authentication) system are complementary. The electronic seal system combined with CA can use CA's authority better to enable the seal system to be universally recognized and promoted by users. The starting point of this paper is to make the smallest improvements to the existing CA system, to improve the safety of the electronic seal system, and to make the seal system used everywhere. This paper believes that the digital certificate interface provided by the existing CA system can be used to construct the seal certificate of the electronic seal system, the seal certificate can be encrypted by MD5(message digest) and DES, and the document can be encrypted by the seal certificate. It's a good solution for the seal system combined with CA system and protecting the seal certificate. Especially, the CA system doesn't need to be changed a lot. Also, it improves the system's expansion and integration. In the end, a word example in the seal system is given and applied to the actual projects.In this paper, a case on the word is realized, but the other signature file formats also need further study. Meanwhile, the seal system structure is complicated, and the data structures and algorithms are different between the enterprises. So it's difficult to authenticate for enterprises. Hope that there will be a standard norm to make all kinds of seal system unified, to combine the seal system and CA based on the government, and to develop the electronic seal system combined with CA system.