摘要电子邮件已经成为了社会生活中不可缺少的部分，但是，不受欢迎的“垃圾邮件”给电子邮件系统和用户带来了诸多不便，而且已经成为一种公认的危害。除了各国政府在法制上出台相关的管理条例以外，反垃圾邮件网关已经成为当前迫切的需求。需要采用专门的邮件过滤设备来对邮件进行净化。我们面向各级政府机关、企事业单位、电子邮件运营商，推出ASF反垃圾邮件网关。这是一套高速度,高可靠性,高安全性,可移植性好的与平台及邮件系统无关的产品。该系统可监控进出企业邮件服务器的电子邮件，检查其间的垃圾邮件，管理员可合理地控制网络流量并进行垃圾邮件过滤。管理员和用户各自可以设置垃圾邮件的自主定义、处理以及其他的相关信息。关键字：反垃圾邮件，网关，过滤，RBLAbstractEmailhasbecometheoneofthemostimportantfactorsinoutmodernlife.Atthesametime,spamcameintobeingandmadethelifeofthepeopleinconvenient.Itisnecessaryfortheanti-spamgateway,whichisequippedwiththespecialfilterstopurifytheincomingemail,toprotectourusuallifeinadditiontotherelatedrulesofthegovernment.TheASFanti-spamemailgatewayisoneofourproducts,whichissuitableforlotsofstaff,suchasgovernments,businesses,telecomoperationcompaniesetc.Theanti-spamemailgatewayishighspeed,reliable,highsecurityandplatformindependent.Itisoneofthegateway’sfunctionsthatcheckingtheemailscomingintoorgoingoutoftheemailserverofanycompanyandthenitwillpickupthespamamongthemandreporttheresult.Thepersonwhoisinchargeofthenetworkwilleasilycontrolthetrafficofthenetworkandfilterthespam.Boththeoperatorsandtheuserswilldefinetheirownrulestofileremails.Keywords:Anti-spam,gateway,filter,RBL目录第1章反垃圾邮件网关系统简介..............11.1序论......................................11.1.1什么是反垃圾邮件网关系统...............11.1.2反垃圾邮件系统的发展...................11.1.3研究目的和意义.........................31.1.3.1垃圾邮件是目前网络上的重要公敌......31.1.3.2反垃圾邮件是国际上热门话题..........51.1.3.2.1微软新推出反垃圾邮件技术........51.1.3.2.22004国内首次反垃圾邮件技术研讨会在京召开.....................................61.1.3.3市场上反垃圾邮件产品现状............8第2章反垃圾邮件网关系统的关键技术...........92.1关键技术...................................92.1.1反垃圾邮件技术三个方面..................92.1.2反垃圾邮件技术的主要过滤方法............9第3章需求分析..............................113.1编写目的..................................113.2项目背景..................................113.3任务概述..................................113.3.1目标..................................113.3.2质量需求..............................113.4功能需求..................................113.4.1功能特性需求..........................113.4.2功能需求描述..........................123.4.2.1过滤功能..........................123.4.2.2管理功能..........................123.4.2.3监控功能..........................123.5性能需求..................................123.5.1时间特性..............................123.5.2适应性................................133.6运行需求..................................133.6.1用户界面..............................133.6.2软件接口..............................133.6.3硬件环境..............................133.6.4软件环境..............................13第4章概要设计.............................144.1开发环境..................................144.2总体架构..................................144.2.1ASF所处地位............................144.2.2命令循环流程...........................154.2.3核心过滤流程...........................
