Secure E-mail Transmission System

The problem of network security has become more and more important in construction of information network. With the development of the Email, the security of the Email has become a hot spot in the field of network security.According to the security situation of the Email in the Internet or the Intranet, this paper establishes a model of the Security Email Service System(SESS) under the basis of analyzing of secure Email. It gives a new scheme of the project designed in detail, discusses detailedly the requirement of security services, security data model design of SESS. It also considers application requirement, design and security analysis of cipher scheme under offline. Finally it can provide services of confidentiality, integrity, authentication based on certification, digital signature and perfect subsystem of key management. This system can send Emails point-to-point and exchange Emails in groups. So this system can be applied in the surroundings of Internet or Intranet.