【作者】 徐玉伟；

【导师】 赵文静；

【作者基本信息】 西安建筑科技大学 ， 计算机应用技术， 2007， 硕士

【摘要】 自从互联网普及以来,电子邮件逐渐成为人们生活中便捷的通信手段之一。然而,随之产生的垃圾邮件像瘟疫一样蔓延,污染网络环境,占用大量传输、存储和计算资源,影响了网络的正常运行。业内人士分析:一旦垃圾邮件占到互联网总数据流量的三分之一以上,将会造成巨大的存储需求,甚至对信息安全系统的有效性构成威胁。如何有效地治理垃圾邮件问题是全世界共同面临的一道难题,也是目前互联网上急待解决的问题。虽然目前某些系统采用一些传统的技术过滤垃圾邮件,但这些技术都很多不足之处。所以,研究设计一种有效的垃圾邮件过滤系统具有十分重要的意义。论文针对当前垃圾邮件大量泛滥的现状,研究了国内外大量反垃圾邮件文献,综合分析了国内外各种流行的垃圾邮件过滤方法,尤其是对协作式反垃圾邮件方法进行了深入的研究。在比较和分析现有的协作式垃圾邮件过滤系统的基础上,提出了一种基于P2P-Chord网络的协作式反垃圾邮件系统模型。该系统由服务器网络和客户端两部分构成。系统的工作流程:首先设定系统的CopyRank阈值,通过统计协作式过滤P2P-Chord网络中各种垃圾邮的CopyRank值,如果统计出来的CopyRank值高于设定的阈值就判定为垃圾邮件,反之为正常邮件。为了防止垃圾邮件发送者通过改变邮件的内容的方式来逃避过滤器,论文在客户端和服务器端分别采用了Nilsimsa和Checksum指纹算法来生成指纹的方式来解决该问题。我们的客户端插件中集成了Bayesian过滤器,这样邮件用户就可以根据以往的邮件在本地过滤垃圾邮件而无需将邮件指纹发送到协作式过滤社区,这样大大降低了网络的通信开销。目前实现了原型系统—AntiSpam和Outlook 2003客户端插件AntiSpamClient,实验结果表明该系统有较好的垃圾邮件过滤性能。更多还原

【Abstract】 Since the popularity of the Internet, e-mail has gradually become one convenient means of communication in people’s lives. However, the resulting spam spread like a plague, pollutes network environment, takes up much of transmission, storage and computing resources, and affects the normal operation of the network. Inners analyse: once spam accounted for a third of the total flow of Internet data above, will cause enormous storage requirements, and even the effectiveness of information security systems is posed a threat. Today,how to effectively deal with spam issues facing the world is a difficult issue, also it is a currently on the Internet problem which is in urgent need to be solve.Although some systems use some traditional spam filtering technologies, but these technologies are a lot of deficiencies. Therefore, the research and design an effective spam filtering system is of great significance.This paper focuses on view of the current massive flood of spam status quo,and studies the large number of anti-spam literature at home and abroad, comprehensive analysis of various popular spam filtering method at home and abroad,especially for collaborative anti-spam method conducted in-depth research. On the basis of comparison and analysis of existing collaborative spam filtering system, a network based on P2P-Chord of collaborative anti-spam system model is presented. The system has two parts: server network and clients. The workflow of system: System CopyRank first be set threshold, through statistics of various spam of CopyRank values in collaborative filtering P2P-Chord network, if statistics of CopyRank value is higher than the threshold be set, the e-mail will be judged spam, contrary to the normal mail. In order to prevent spammers by changing the contents of the e-mail to avoid filters, this paper clients and server were used Nilsimsa and Checksum fingerprint algorithm to generatethe fingerprint to solve the problem. Our client plugin integrated Bayesianian filters, so mail users can filer spam in local, according e-mails in the past without fingerprintswill be sent to the collaborative filtering community, so that a network greatlyreduces the communication overhead. A prototype system-AntiSpam and Outlook 2003 client plugin-AntiSpamClient now are realized at present.The experimental results showthat the system has good spam filtering performance.更多还原