基于socket的局域网聊天工具，数据包经过des加密，实现了上下线通知，单聊，群聊，文件传输等常用功能。-Socket-based local area network chat tool, the data packet through the des encryption, notification of on-line and offline, single chat, group chat, file transfer, and some other common functions

本程序可以对CPU卡初学者是个很好的工具，可以对CPU卡分别进行：寻卡、取随机数、DES加密、外部认证、建立文件等。即使对其不怎么了解也可以很快入门。-This procedure can be CPU card is a good tool for beginners, you can separately CPU card: Find cards, take a random number, DES encryption, external authentication, document,