网络技术渐渐成熟,电子邮件技术也越来越成熟。现今,电子邮件(E-mail)是Internet上使用最为广泛的一种服务。
本论文设计并实现了一个电子邮件收发系统,该系统可以使用户更加方便的管理电子邮件,用户不用登陆网页,就可以收取和发送电子邮件。该系统主要分为三部分:用户设置、发送邮件和收取邮件。它采用C/S设计模式,服务器端是SMTP服务器和POP服务器,客户端是邮件收发程序。用户设置部分是注册用户,把用户信息存储起来。发送邮件部分是基于SMTP(Simple Mail Transfer Protocol,简单邮件传输协议)与SMTP服务器进行对话。收取邮件部分是基于POP3(Post Office Protocol version 3,邮局协议)与POP服务器进行对话。电子邮件收发信息不只支持英文,而且支持中文。由于RFC882限制电子邮件的文本只能采用US ASCⅡ字符集,所以本系统采用MIME编码解码,扩展信件规范。最后,对该系统进行了测试。
论文分别从系统涉及的基础知识、系统的设计与实现和系统实现采用的关键技术进行详细说明。论文最后还对全文作出了总结。
关键词:信体结构,SMTP,POP3,MIME, 编码,解码
A Design and Implement of Simple Mail System
Abstract
Network technology is becoming more and more nature, and E-mail technology is developed fast. Nowadays, E-mail has become a most used service on Internet.
The dissertation designs and implements a Simple Mail System. The users can easily manage the E-mail by using this system. They can check and send E-mail without landing website. The system includes three main modules: User setting, E-mail sending, E-mail checking. It uses a C/S architecture. The server is a SMTP server or a POP server, and the client is a sending and checking E-mail tool. The part of User setting is used to register users, it storage the information in the local disk. The part of E-mail sending is communicating with the SMTP server by Simple Mail Transfer Protocol and the part of E-mail checking is communicating with the POP server by Post Office Protocol. The Simple Mail System support not only English, but also Chinese. Limited by RFC822, the text of E-mail can only use ASCⅡ character set. Thus, this system makes use of MIME to encoding and decoding, and expanding mail norms. In the end, I make a testing for the Simple Mail System.
The dissertation introduces the system from the following aspects: the purpose of the design, the design and the implement of the system, the key technologies, and so on. Finally, it makes a summary of the dissertation.