【作者】 杨春明；

【导师】 屈玉贵；

【作者基本信息】 中国科学技术大学 ， 通信与信息系统， 2008， 博士

【摘要】 无线传感器网络是一种特殊的Ad-hoc网络,通常包含大量的低功耗的微型传感器节点,依靠传感器节点之间的相互协作,以无线多跳方式完成通信,网络不依赖任何的固定设施,具有自组织和自管理的特性。这种特殊的组网方式使得无线传感器网络广泛的应用于目标跟踪、关键区域检测、危险环境中的科研开发等领域。然而,无线传感器网络的一些特性,比如能量受限、体积受限等,给网络的时间同步算法设计提出了严峻的考验。本文分别围绕与时间同步相关的安全问题、能量有效问题展开深入研究,提出了适用于动态无线传感器网络的安全时间同步算法和能量有效的无线传感器时间同步算法。本文的主要工作和创新点归纳如下:适用于动态无线传感器网络的安全时间同步算法时间同步技术是无线传感器网络中非常重要的一项基础服务,是实现定位、数据融合、移动目标跟踪等技术的基础。然而由于无线传感器网络自身的特性,使得它的时间同步过程容易遭受恶意节点的攻击。为此,本文提出一种适用于动态无线传感器网络的安全时间同步算法,此算法可以阻止来自网络内外的恶意节点的攻击,并且在一些时间同步的性能参数上都有着比其他时间同步算法更优越的表现。能量有效的无线传感器网络时间同步算法与一般的计算网络不同,在无线传感器网络中,能量的有限性是一个尤为突出的问题。同时无线传感器网络是一个面向应用的,需要通过节点之间的协作完成某一特定任务的网络,因此保持全网能耗的均衡来维持网络的连通性是十分重要的。如何节省节点的能量消耗以及如何均衡网络中节点的能量消耗,从而延长整个网络的生命周期,是无线传感器网络研究中面临的首要挑战,也是该领域一个持久的研究热点。本文提出一种能量有效的无线传感器网络时间同步算法,该算法可以节省无线传感器网络时间同步的能量消耗,同时又不影响其他的性能参数。无线传感器网络硬件试验平台本文设计和实现了无线传感器网络试验的硬件平台,包括传感器节点、网络适配器以及编程器。并且在此平台基础上,进行了时间同步算法的试验,验证了上述无线传感器网络安全时间同步算法的可行性;另外进行了有关IPv6的一系列试验,验证了该试验平台可以稳定运行于CNGI网络中,成为CNGI网络的一个组成部分。论文阐述的这些方法和思想都经过了理论分析和仿真实验的验证,证明了其可行性。这些结论可以应用到未来相关产品的开发中,以提高网络的灵活性、有效性和扩展性。更多还原

【Abstract】 Wireless sensor network (WSN) is a special type of Ad-hoc networks. It usually consists of a large number of tiny low-power sensor nodes. The communications between the sensor nodes rely on mutual collaboration in wireless multi-hop manner, and therefore the network is self-organized and self-managed without any infrastructure. Because of the special type of networking, wireless sensor network has been widely used in target tracking, monitoring of critical infrastructures, and scientific exploration in dangerous environments and etc. However, the characteristics of WSN, such as energy constrained, volume constrained and etc, challenge to the design of time synchronization algorithm. Focused on the time synchronization algorithm, this paper studied the problems about security and energy-efficiency, and proposed a novel algorithm of secure time synchronization for dynamic wireless sensor networks and an energy-efficient time-synchronization algorithm for wireless sensor networks.The major job and creative ideas of this thesis are listed as follows:Firstly, a novel algorithm of secure time-synchronization for dynamic wireless sensor networks was proposed. As we all know, the technique of time synchronization is one of the crucial basic services of wireless sensor networks. And it is required in many applications like localization, data aggregation, mobile object tracking, etc. But the characteristics of WSN lead that its synchronization process can be easily attacked by the malicious nodes. Therefore, a novel time synchronization algorithm for dynamic wireless sensor networks was proposed in this paper, and it can prevent the time synchronization process of WSN from the attack of the malicious nodes. Compared to the other time synchronization algorithms, it has prime advantages in the main performance parameters.Secondly, WSN is very different from the other networks, and the energy limitation is the biggest problem. WSN is application oriented, which needs the cooperation between the nodes to accomplish some special tasks. So it is very important to maintain the connectedness of WSN. The ways and means to reduce the energy consuming of the nodes, to balance the energy consuming between all the nodes, and to prolong the life of WSN, are the main challenges during the research on WSN. An energy-efficient time synchronization algorithm was proposed in this paper, and it can reduce the energy consuming during the synchronization process of WSN without any negative influence on the other performance parameters.Thirdly, we designed and carried out the experimental hardware platform of wireless sensor networks, which includes the sensor nodes, the network access point, and the programmer. Based on this platform, we made some experiments about time synchronization algorithm and IPv6. The former experiment indicated the feasibility of the secure time synchronization algorithm referred above. And the latter proved that this platform can work well with the CNGI network stably as a component part of CNGI.The novel ideas and methods in the dissertation have been studied and verified through theoretic analysis and simulations, which have showed the feasibility. These results can be applied and developed into the future related products to enhance the flexibility, efficiency and scalability.更多还原