"基于旁路的Web访问监控系统设计与实现"

Abstract: This graduation thesis explores the design and implementation of a web access monitoring system based on the bypass method. In environments like laboratories or offices, administrators often desire for students or employees to focus on their tasks without distractions from irrelevant web pages or websites. Therefore, when someone tries to access such sites, the server intercepts the attempt and sends a pre-prepared page curated by the administrator, thus preventing the interruption and enhancing productivity. The paper begins by discussing the intrusion and hazards posed by malicious websites on regular network operations. By setting the network card to promiscuous mode, data packets can be captured effectively for network monitoring. An IP packet filtering module is used to distinguish HTTP packets such as GET and POST, extracting URL addresses which are then matched against a pre-prepared database of blacklisted websites to identify and intercept irrelevant sites, thus purifying the network environment. Furthermore, extensive performance and functionality tests were conducted on the system to ensure its completeness and optimize its performance. Keywords: promiscuous mode, data packet capture, web filtering.