Secure Email System

Now Email is one of the most important applications on Internet. With the development of network, using email has become an important method of people's communication, and the security of email has been paid great attention to by more and more people. But just like the message on postcards, all the message of email is open and can be gotten while being tranferd between machines. Everyone who can use computers can see the content of email. Moreover, the content of email can be modified by someone while other people hardly know that, and somebody with malignity can send an email imitating another person. The information transferred through email is so tender that how to protect the security has been highly concerned by many people. Because traditional email that we usually use has little security, it is a very important issue for us to provide secure email service.In this paper, a secure email system is proposed, including the secure server named MailGod and the secure client, JiMaoXin. This system can provide good security services while transfering email between server and client.Basically, the contributions of this paper are as follows:Propose a secure email system with complete functional performance. The MailGod server and JiMaoXin client presents the full solution of email security.Keeps to the international standards and has entire intellectual property. In MailGod and JiMaoXin, the architecture and the service keep to the email protocols, such as SMTP, POP3, MIME and so on. In addition, both of them strictly keep to the PKI standards, and act according to the prescripts of the national secure department.Implement a secure email server with powerful function. MailGod server provides not only various functions with supporting of secure module extension but also simple and convenient configurations.Implement a convenient email client with powerful funcion. JiMaoXin client not only has traditional email clients' characteristics but also provides Digital Signature and Data Encryption based on PKI standards.Digital watermark technology is used in server system. In MailGod, all of the operations are recorded in system log, and digital watermark technology is used to ensure authoritativeness, accountability and integrity.A technology of integrating address book and certificate management is used in client system. In JiMaoXin, users can conveniently manage certificates through the familiar address book without learning the knowledge of cryptography.A nested encryption is innovated in client system. In JiMaoXin, more than one public key can be used in encryption, so that all owners of those public key should be present in decryption. When used in some special situations, such as public bidding of government, this technology can provide publicity, impartiality and equity.In April 2003, the secure server and client passed the authentication of technological experts.The committee regarded this system as the first multi-functional secure email system with intelligent gateway and disaster recovery system.In September 2003, the technique innovated in JiMaoXin client was applied for the inventive patent, which was named as a method of multiple encryption.In November 2003, as the pivotal part in the secure network-platform of E-Government and E-Commerce, MailGod server and JiMaoXin client won the first-class award of technological progress in Chengdu.In a word, the implementation of MailGod server and JiMaoXin client has entire intellectual property. It effectively solves secure problems in traditional email system and has profound significance in guaranteeing security of communications.