【作者】 卢磊；

【导师】 刘富强；

【作者基本信息】 同济大学 ， 信号与信息处理， 2007， 硕士

【摘要】 全球微波接入互操作性(WiMAX：World Interoperability for Microwave Access)作为一种极具竞争力的无线接入技术，众多的运营商都在关注着它的进展，并着力将其推向市场。然而由于无线城域网的传输媒介的开放性，安全问题也备受关注，安全机制完善如否，接入控制策略是否合理，已经成为WiMAX网络产品化和市场化成功与否的关键性因素之一，因此，本论文对于WiMAX网络安全机制和接入控制问题的研究具有非常重要的意义。首先，论文针对IEEE 802.16协议中的安全子层，论述了IEEE 802.16-2004和IEEE 802.16-2005标准的安全机制，建立起基站和用户站在认证机制，密钥分配，数据加密这一系列过程中的交互流程。针对该流程进行了安全分析，分析其对经典攻击的响应，通过分析，发现协议对一些安全问题没有给出详细的定义，其认证体系存在一定的缺陷，且移动终端处理能力弱，这些问题都会造成一定的安全漏洞，带来安全隐患。其次，在分析安全漏洞的基础上，引入了无线公钥体系(Wireless Public Key Infrastructure：WPKI)到WiMAX，并针对WiMAX的特点做出了修正和改进，提出了基于WPKI技术的认证机制，基于AES算法的数据传输安全机制，基于SSL技术的基站间安全通信机制，改进了WiMAX系统中的安全体系，并对该安全体系进行了安全和性能分析，分析表明，改进的WiMAX安全体系在一定程度上解决了WiMAX中存在的安全隐患，同时兼顾了移动终端处理能力弱，存储空间小的问题，提高了安全体系的性能。接着，本文对WiMAX系统对接入控制的定义做了分析，对传统蜂窝网络和3G系统的接入控制算法做了全面深入的研究，比较了各种接入控制算法的适用条件和优缺点，针对WiMAX系统的特点，依据接入控制的衡量指标，提出了基于QoS优先级的接入控制机制，并对该机制进行了仿真，仿真结果验证本文算法的有效性和可靠性。最后，文章进行了全文总结，并对未来工作做出了展望。更多还原

【Abstract】 As a highly competitive wireless access technology, WiMAX (WorldInteroperability for Microwave Access) and its marketing are concerned by manyoperators. However, as the opening nature of WMAN’s transmission medium, thesecurity and admission control issues are concerned. How to provide a perfectsecurity mechanism becomes a key problem in WiMAX networking products’marketization. So the research on security mechanism and admission controlalgorithm of WiMAX network is of great significance.First of all, According to security sublayer in IEEE 802.16 standard, thesecurity mechanism of IEEE 802.16-2004 and IEEE 802.16-2005 is discussed first,the process in authentication mechanisms, key distribution, data encryption andestablish between base station and mobile station is established. The mechanism’sresponse against the classic attacks is analyzed. Then, we found that lack ofdefinition on some security problems, the vulnerability of authorization mechanismand the weak ability of the mobile terminal would bring some security problems.Secondly, on this basis, WPKI (Wireless Public Key Infrastructure) isintroduced into WiMAX, and adjustments and improvements are proposedaccordingto WiMAX’s features. We propose WPKI technology for the authenticationmechanism, security mechanism based on the AES algorithm for data transmission,SSL-based secure communications between base station and mobile station. Thesecurity mechanism in WiMAX systems is improved, the performance and securityof this scheme is analyzed. The result shows that our security scheme solves somesecurity problems in WiMAX, while the ablility of mobile terminal is considered toimprove the performance.Then, the paper analyzed the definition of Access Control Mechanism forWiMAX system. Access control algorithms in traditional cellular networks and 3Gsystem is studied, the applicable conditions and the shortcomings of differentalgorithms are compared. According to the feature of WiMAX system, Access control mechanism based on the QoS priority is proposed, and the mechanism is simulated todemonstrate its effectiveness.At last, the summary of the paper is proposed, and the future work is advised.更多还原