阴国富

摘 要:分析讨论无线局域网的安全现状及现有的安全机制存在的问题,主要研究目前常见的安全加密算法WEP,详细阐述WEP加密算法的原理、指出WEP协议自身存在的安全漏洞,并针对漏洞和攻击提出了改进型的WEP加密算法建议,仿真实验表明改进后的加密算法对无线局域网的安全防范有非常好的加强作用。

关键词:无线局域网;安全防范;WEP;加密算法

中图分类号:TP393文献标识码:A

文章编号:1004-373X(2009)20-091-02

Research of WLAN Security Encryption Algorithm

YIN Guofu

(Weinan Teachers College,Weinan,714000,China)

Abstract:As the popularity of IEEE802.11 wireless LAN technology,security issues are becoming increasingly important.a wireless local area network and the commonly used international standard IEEE 802.11 series are introduced,especially for simply discussing wireless LAN security situation.In this discussion,the existing security mechanisms are described.It mainly researches the common security WEP encryption algorithm,explains the principle of WEP encryption algorithm in detail,proposes the existence of serious security vulnerabilities in WEP protocol,and mainly analyzes its security vulnerabilities and vulnerable to a series of attacks which especially is recognized as the most effective way to attack RC4 and FMS,as well as proposes one solution against vulnerabilities and attacks.Experiments show that it strengthens the security of wireless LAN very well.

Keywords:WLAN;security;WEP;encrypiton algorithm

0 引 言

无线局域网(Wired Local Area Ntework,WLAN)作为无线网络的一种接入方式,以其快捷高效,组网灵活,易于移动等特点,得到了广泛应用。无线局域网是指在一个局部区域内计算机之间通过无线链路进行通信的网络。目前无线局域网广泛地应用于企业、金融机构、制造仓储业、机场码头、科研院校等不同领域。无线局域网采用公共的电磁波作为载体进行数据传输,任何人都有条件和可能窃听或干扰信息,存在电磁波泄露或者数据被截听的安全隐患。因此在无线局域网中,网络安全显得尤为重要[1]。

1 WEP算法

无线局域网信息传输系统的安全需求主要包括四个方面:身份认证、数据加密、信息完整性认证、密钥管理 [2]。WEP(Wired Equivalent Privacy)算法试图将无线通信的安全性提高到可以与有线通信相比拟的水平上[3]。在无线电波中传输的协议数据都是密文,窃听者在不知道加密密钥的情况下是无法了解数据内容的,达到了保密性的目的;数据的完整性检验,是对协议数据的完整性保证的手段;非授权的移动用户,没有加密密钥就不能对数据进行访问,达到访问控制的目的。……