Research On Technology Of Monitoring And Filtering LAN Spam

With the rapid development of Internet, people s communication between the Internet isalso becoming increasingly popular. As communication services on the Internet, e-mail hasbeen widely used since its convenient transmission, fast speed and low price. Nowadays it hasbecome the people’s daily life an important part.But while e-mail brought great convenienceto people, it also brought a series of network security issues. One of them is the proliferationof spam.It disturbs people s daily e-mails. And some malignant spam carrying objectionableinformation, phishing sites or Trojan virus will bring serious harm to the recipient. Therefore,in order to reduce network spam, to provide users with a safe recipient environment, it is veryimportant to develop a usable and reliable LAN spam monitoring and filtering system.This paper deeply analyzed the transmission principle of email in the network, on thebasis of this,this paper put forward a set of scheme which has used listening mode andincluded both software and hardware. This paper realized the most basic and importantmodule in the system scheme. Through the testing experiment of actual networkenvironment,the accomplish function of this system scheme is tested as available. It canaccurately monitor and restore the message text in LAN environment, and has achieved theexpected effect on accuracy and memory utilization indicators.The main work of this paper includes:First, this paper described the background and significance of the subject, described theresearch status of spam filtering system in China and abroad. After that, this paper discussedthe basic principles of LAN spam monitoring and filtering echnology.Second, starting from the access position of network, this paper analyzed and contrastedseveral implementation of LAN spam monitoring and filtering system, described thefeasibility and advantages of using listening mode. After determining the network architectureof system, this paper further determined the system’s software configuration,then based one-mail s restoration process,analyzed and designed e-mail s restoration module which is veryimportant in detail, then used network security tool which named Libnids to achieverestoration of e-mail.Finally, the function and RAM usage amount of implemented module was tested in thispaper.The scheme of LAN spam monitoring and filtering put forward by this paper only needsa few resource from users,makes little influence on normal network communication,its accessmode is also ease and flexibility.According to the actual need to the scheme,the design of system has strong scalability and maintainability.In addition, this paper addressed a key technology: how to manager numbers oftransferring e-mails at the same time in LAN.