随着Internet的迅速普及, 电子邮件已经成为现今Internet上最流行的应用之一。它被广泛应用于商业、政府部门、大学、中学、家庭等方面^[1]。电子邮件在为人们工作、学习和生活提供便利通信手段的同时, 也为病毒、黑客程序、****、反动、暴力、迷信等不良信息的传播提供了重要载体^{[2, 3]}。而这类携带不良信息的邮件, 正是我们所熟知的垃圾邮件, 它给Internet用户、网络管理员和ISP(Internet服务提供者)带来了无尽的烦恼。虽然陆续推出几款邮件过滤软件, 但在对比几种邮件过滤软件原理后发现, 目前的邮件过滤方法或多或少地存在着语义缺失问题, 当垃圾邮件发展到一定程度后, 邮件过滤算法或过滤系统都将难以应付。而且现阶段多数垃圾邮件主体或发信人地址常动态改变, 而其正文及附件内容却基本一致, 对于拥有数万用户的大型局域网而言, 垃圾邮件普遍以群发的方式在网内传播。针对这些特点, 有必要引入新的思想, 来改进原有的解决方案深圳翻译公司报价。

With rapid popularization of Internet, Email has become one of the most extensively used applications on the Internet nowadays. It is widely used in companies, government organs, colleges and universities, middle schools and families, etc.^[1] While serving as a convenient communication approach to facilitate people’s work, study and life, Email also provides an important carrier for spreading virus, hacker programs, porn, reactionary and superstitious information^{[2, 3]}. These Emails carrying unhealthy information are known as spam, which has been a constant annoyance to Internet users, network administrators and Internet service providers (ISP). There are now a couple of filtering software programs available on the market, yet we found by comparing their theories that current filtering software programs are more or less having the problem of absence of semantics. Therefore, when the spam develops to a certain degree, these Email filtering algorithms or filtering systems may not be able to handle them. Besides, the sender address of most spam today varies in a dynamic way, yet contents of the text or attachment are the same. In large-scale LAN that includes tens of thousands of users, spam usually spreads itself across the network by means of mass mailing. In consideration of these characteristics, it is necessary to introduce new theory to improve existing solutions.