Secure Email Server System

Now Email becomes the most used application on internet. With the development of network, using email has become an important method of people's communication, People use it to transfer their private letters, companies use it to transfer their business plans and data, governments use it to transfer their document, etc. Email is everywhere! However, the traditional Email Systems have some insecure factor, The traditional Email Systems are not suitable for transferring important information. But just like the message on postcards, all the message of email is open and can be gotten while being tranferd between networks. 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. Because traditional email that we usually use has little security,it blocks our country's information industry's progress. The information transferred through email is so tender that how to protect the security has been highly concerned by many people. In this paper, a secure email server system is proposed.By using the server,this system can provide good security services while transfering email between server and client. Basically, the contributions of this paper are as follows: 1) Propose a secure email server management system with complete functional performance. The MailGod server presents the full solution of email security. 2) Keeps to the international standards and has entire intellectual property. In MailGod, its architecture and function service keep to the email protocols,such as SMTP, POP3, MIME and so on. In addition, about the security it has entire intellectual property according to the prescripts of the national secure department. 3) 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. 4) 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. This paper introduces the basic theory of email transmission and some protocols of Email System, such as SMTP, POP3 and MIME. It analyses and evaluates some popular secure character and correspond technology of Email. At last, The paper discusses the design and implementation of secure email server system.The paper effectively solves several secure problems in traditional Email System. It is suitable for domestic users. It has profound significance in guaranteeing our country's communication security of email.