邮件代理端软件的设计与开发：基本要求可以完成邮件编辑，与标准邮件服务器的连接，发送并且下载邮件，进一步要求邮件管理，邮件的加密解密传送。

设计提示—学习邮件客户端和服务器之间通信协议SMTP和POP3协议的规范，选择一特定的邮件服务器（自己安装一个或选择一公共邮件服务器）建立邮件账户，编程实现与服务器的通信建立、利用SMTP协议完成邮件发送，利用POP3完成邮件接收。-E-mail proxy client software design and development: the basic requirements to complete e-mail editor, and the standard mail server, send and download e-mail, and further requested e-mail management, encryption and decryption of messages sent. Design Tips- Learn e-mail communication between client and server protocols SMTP and POP3 protocol specification, select a particular mail server (own or choose a public install a mail server) create a mail account, the programming to establish communication with the server using SMTP mail protocol completed, complete the e-mail using POP3 to receive.