计算机网络安全中的防火墙技术和端口扫描技术毕业设计.doc

计算机网络安全中防火墙技术和端口扫描技术 钟德懿 （西南林学院 计算机与信息科学系，云南 昆明 650224） 摘要：进入21世纪，随着Internet的发展，以Internet为平台的信息技术进入了新的时代，而网络安全技术作为网络技术中的重要组成部分也迎来了新的挑战。网络安全技术是伴随着网络的诞生而出现的, 90年代在国外获得了飞速的发展近几年频繁出现的安全事故引起了各国计算机安全界的高度重视，计算机网络安全技术也因此出现了日新月异的变化。VB6.0的环境下开发的，主要应用了WINDOWS操作系统下的网络编程接口和VB6.0里的Winsock控件，程序中调用了大量的WINDOWS API。在文中具体描述了实现过程中采用的有关的技术，并给出了程序中的各个功能模块以及设计思路和重要代码。 关键词：网络安全 端口扫描 防火墙 网络协议 WINSOCK WINDOWS API　 The Technology Of Firewall and Ports-scan in Computer Network Security Deyi Zhong (Dept. of Computer and Information Science, Southwest Forestry College, Kunming, Yunan, 650224, China) Abstract:Entering 21st century, with the development of Internet, The information technology taking Internet as platform entered new era, and network safe practice meet and bring the new challenge as important component of network technology too,The technology of network security has come forth with the network born. It developed rapidly overseas in the 1990’s. The secure accident came recently caused to be placed importance by compute secure filed. So the technology of network security has taken a new look. This paper mainly discusses all kinds of technology of network security at first, especially about the technology of firewall and ports-scan. Based on correlative theory I develops a simple program about local listening, ports-scan, Ping Host-computer. this Procedure develop under the environment of VB6.0 , Use WINDOWS network programming interface and Winsock controlling part of VB6.0 of operating system mainly, have transfered a large amount of WINDOWS APIs in the procedure . Relevant technology adopted in the course of describedding and realizes concretly in the article, and provide each function module and the mentality of designing and important code in the procedure . Keywords:Network security; Ports-Scan; Firewall; Network Protocol; Winsock; Windows API 目 录 1 前言 1 2 网络协议与网络安全中的主要技术简介 1 2.1 网络协议 1 2.1.1 TCP/IP协议 2 2.1.2 PPTP协议 2 2.1.3 L2F协议 3 2.1.4 L2TP协议 3 2.1.5 IPSec协议 3 2.1