The Design And Implementation Of Security E-mail System Based On CPK

The convenience and quickness of e-mail makes it widely applied on the internet, besides it is also the most important tool for the exchange of information. With the rapid growth of dependence on e-mail, the demand of authentication and confidentiality is also increasing. The openness of the Internet makes e-mail transmission on the Internet easily to be attacked. Secure messaging refers to the ability to provide data confidentiality, data integrity, data origin authentication, and non-repudiation of origin services for email. In order to deliver the e-mail from the sender to the receiver securely, there are many secure email systems such as PGP mail and S/MIME. Most of them rely on Public Key Infrastructure (PKI) that is complicated in composition and operation providing public and private key pair as the essential to encryption and digital signature. In addition, PKI is too difficult for the average users. It requires a tremendous overhead in terms of setting up a public key: locating a certificate authority that can issue a digital certificate, publicizing the public key to others, renewing the certificate when it expires, and so on.Elliptic Curve Cryptography Combined Public Key is first proposed by a famous information security expert XiangHao Nan in 1999. It is a new centralized key management mode to resolve the large-scale key management problem through"infinity"public keys produced with few"seeds". It need not to set up the third on-line certificate agent, requires less key storage space, and consumes smaller computing capability.This paper mainly studies a new secure e-mail scheme based on Elliptic Curve Cryptography Combined Public Key Algorithm. Firstly, I introduce some related e-mail protocols. Then I introduce the knowledge about Elliptic Curve Cryptography Combined Public Key Algorithm. Finally, a new secure e-mail scheme based on Elliptic Curve Cryptography Combined Public Key Algorithm is designed and implemented. The secure e-mail system is especially suitable for the application in private network and intranet environment. The functions such as authentication, encryption, and signature are gotten to form a plug-in embedded into Office Outlook, Outlook Express, Foxmail Webmail, et al. By analyzing the security and performance, the results indicate that this system is secure, efficient, and easy to be used.