基于混沌密码学的无线局域网加密协议改进

发布时间：2018-03-25 18:37

本文选题：无线局域网　切入点：WPA/WPA2　出处：《东北大学》2014年硕士论文

【摘要】：无线局域网随处可见,已经成为我们生活的一部分,但无线网络安全空间仍然乌云密布。2013年的“棱镜门”事件已经持续发酵了一年多,这让人民震惊,开始重视个人网络的安全问题。无线局域网的第二代数据保密协议采用的是WiFi保护性接入(WPA),采用AES算法作为无线局域网的高标准数据加密协议。目前,人们已经发现了WPA的一些漏洞。混沌密码学以其对初始条件的敏感性、长期不可预测性和良好的伪随机性等特性,在网络安全应用领域迅速发展。混沌系统所具有的这些良好特性却恰好与保密通信及密码学的基本要求高度吻合,混沌模型所独有对初始条件的敏感性以及长期不可预测性正好满足密码系统设计的扩散和混淆原则。所以本论文将采用混沌理论中的相关知识来继续改进完善WPA/WPA2协议,以便将这些安全隐患消灭在萌芽阶段。由于无线局域网使用的是无线传输,容易受到窃听,而对无线局域网的攻击主要是集中在WPA协议中采用的AES算法。故在本论文中使用混沌理论中的Logistic模型对AES加密算法进行了改进,借此来加强WPA协议的安全性。本论文的主要工作包括：(1)针对AES算法中密钥扩展模块的两处不足,本论文采用改变混沌系统中初始值的方法,把每次迭代值作为每一轮的子密钥,以此降低各轮子密钥之间的线性相关性,也就消除了从某个密钥推测全部密钥空间的威胁。(2)针对AES算法中的初始密钥是事先固定的,可以从此推理出后续的密钥部分,本论文利用混沌系统具有好的伪随机特性和对初始值具有高度敏感性,把混沌系统产生的数据流转化为AES算法的初始密钥,这样对初始密钥的安全和随机性有较大的保障,同时也加强了加解密算法的复杂性。(3)对采用混沌理论改进后的AES算法在无线局域网中进行了相关测试实验,在密钥空间、随机性、效率和敏感性等方面与原AES算法进行了分析对比,以此为未来无线网络的安全做尝试。随着大数据、云计算和物联网的到来,无线网络的应用会加速发展,高标准的无线网络安全问题已是迫在眉睫,基于混沌密码良好特性的无线网络必将会开花结果,为我们的网上冲浪保驾护航,为物联网的实施奠定基础。
[Abstract]:WLAN is everywhere and has become a part of our lives, but the wireless security space is still overshadowed. The Prism Gate incident of 2013 has been going on for more than a year, which has shocked the people. The second generation data security protocol of WLAN adopts WiFi protected access protocol and AES algorithm as the high standard data encryption protocol of WLAN. Some vulnerabilities of WPA have been discovered. Chaotic cryptography is characterized by its sensitivity to initial conditions, long-term unpredictability and good pseudorandom. With the rapid development of network security applications, these good features of chaotic systems coincide with the basic requirements of secure communications and cryptography. The sensitivity of the chaotic model to initial conditions and the long-term unpredictability can meet the diffusion and confusion principles of cryptographic system design. Therefore, this paper will continue to improve the WPA/WPA2 protocol by using the relevant knowledge of chaos theory. In order to eliminate these security risks in the embryonic stage. Because WLAN uses wireless transmission, it is vulnerable to eavesdropping. The attack on WLAN is mainly focused on the AES algorithm used in the WPA protocol. Therefore, in this paper, the Logistic model of chaos theory is used to improve the AES encryption algorithm. In order to enhance the security of WPA protocol, the main work of this thesis includes: 1) aiming at the two shortcomings of the key expansion module in the AES algorithm, this paper adopts the method of changing the initial value of the chaotic system and regards each iteration value as the sub-key of each round. In order to reduce the linear correlation between the keys on each wheel, the threat of speculating the entire key space from a certain key is eliminated.) the initial key in the AES algorithm is fixed in advance, and the subsequent key part can be deduced from it. In this paper, the chaotic system has good pseudorandom and high sensitivity to the initial value, and the data stream generated by the chaotic system is transformed into the initial key of the AES algorithm, which ensures the security and randomness of the initial key. At the same time, the complexity of encryption and decryption algorithm is also strengthened. The AES algorithm, which is improved by chaos theory, is tested in WLAN, which is random in key space. Efficiency and sensitivity are analyzed and compared with the original AES algorithm in order to make a trial of wireless network security in the future. With the advent of big data, cloud computing and the Internet of things, wireless network applications will accelerate development. The problem of high standard wireless network security is imminent. The wireless network based on the good characteristics of chaotic cipher will certainly blossom and will protect our network surfing and lay the foundation for the implementation of the Internet of things.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN925.93;TN918.4

【相似文献】