Study And Realization Of Email System Based On OpenPGP

Email technology gradually has become one of the network services with the Internet more and more important in daily life today. With the convenient, fast and other features, the majority of Internet users would choose to use Email as a means of information dissemination.In practice, most email systems are cleartext which making some people with ulterior motives could easily access the user's e-mail messages, and even transform or tampered with the message content. Therefore, the security of e-mail is more and more prominent.This article focuses on the OpenPGP protocol encryption technology based on e-mail messages in the information system security issues to develop a Web mail system security and enhance the security of e-mail. JavaMail is a Java API used to receive and send email via SMTP, POP3 and IMAP. OpenPGP is the most widely used email encryption standard in the world.After the development of e-security e-mail history and background, this paper introduces the E-mail transmission protocol and JavaMail. Then discuss encryption, such as DES, ADS, IDEA, RSA, MD5 and so on. Analyze the trust model of OpenPGP in detail their existing problems, and puts forward these problems corresponding solutions. In the cases without modifying source with RIPEMD algorithms insteads of the MD5 algorithms which is unsafe in OpenPGP. RIPEMD algorithm would be added in OpenPGP protocol toolkit to achieve the e-mail encryption, decryption and other functions. Based on the theory, design an E-mail system which implements encryption to send and receive messages and decrypt messages and so on.This paper puts PGP encryption technology applying to JavaMail E-mail systems and maintains the characteristics of PGP which is security and ease of implementation.In this paper, it used RIPEMD instead of MD5 algorithm which has been unsafe to ensure the message is confidentiality, integrity, authentication and non-dependence.