Research On Some Issues Of Malicious Node Attack In Wireless Sensor Networks

The development of wireless sensor networks is motivated by evolvement ofwireless communications, microelectronics, sensing and embedded systemstechnologies. A wireless senor network consists of spatially distributed sensor nodeswhich deployed in sensing area. These nodes are self-organized into a multi-hopnetwork by wireless communication to sense, monitor and process information of thephysical or environmental conditions and feedback the real-time data to the observer.Wireless sensor networks give the people a powerful ability to perceive the objectivephysical world, and connect the objective physical world with the transmissionnetwork tightly. People could gain the most real and effective information from thephysical world by wireless sensor network. Wireless sensor network is widely usedin the military, industrial and consumer applications such as battlefield surveillance,industrial process monitoring and control, environmental monitoring, precisionagriculture and so on.Wireless sensor networks have characteristic of self-organizing, large-scale,distributed. Sensor nodes have very limited resources of computing, storage,communications and energy, and need undertake sensing and routing tasks. Thesefeatures of wireless sensor networks bring new challenges for network security.Meanwhile sensor nodes are often deployed in an open, unattended even hostileenvironment, such as in the military fields. So in these applications, the assumptionthat all the nodes are cooperative and credible will not be true. The most serioussituation is that nodes suffer physical attacks. The adversities capture the sensornodes and extract all the information including security data like secret key, and thentransformed them into malicious nodes to launch various attacks. These maliciousnodes could bring serious threat to our networks, because these nodes havelegitimate keys and private information while the key mechanism based securitycertification schemes could not detect these malicious nodes. Thus, these nodescould launch various inside attacks. The adversities could launch node cloningattacks in the deployment. In the routing phase, they can attack the routing protocols.When collecting data, they may launch the false data injection attacks to cheat andconfound the observer. This thesis will research on defence of the threes attacks andestablish a basic security framework for wireless senor network. The research works is outlined as follow:1) Clone attack is that the adversary uses a compromised node to product manyclones and then inject them into the network to launch various inside attacks. Inthis thesis we propose two schemes based on random seeds. Every node'slocation claim is forwarded to the verification nodes which are selected by usingthe preloaded random seeds. When the verification nodes collection two clones'location claims, it will detect the clone attacks. In the analysis, we prove that ourapproached can achieve high detection ratio with low memory overhead.2) Virtual coordinate system (VCS) based routing provides a practical, efficientand scalable means for point-to-point routing in wireless sensor networks.Several VCS-based routing protocols have been proposed in the last few years,all assuming that nodes behave correctly, does not consider the security.Especial the VCS are vulnerable to numerous attacks. We introduce a monitorand verification mechanism to detect the unmoral operations to protect anestablishment of a real VCS.3) We propose two traceback schemes for defending false data injection attacks.The first scheme is based on probabilistic edge marking. When a packet isforwarded to the sink, the routing edge is marking in the packet head withcertain probability; the sink could construct a attack path by collecting enoughmessages. Then we propose another approach based probabilistic packetmarking and packet logging which can reconstruct attack path more quickly andreduce the communication overhead with low memory overhead.