Research On Security Of Ultra-Wide Band Wireless Network

The emerging technology of ultra-wide band (UWB) high-speed indoor wireless communication has attracted world wide attention. With the merits of high data rate, low system power cost and multi-path immunity, compared with general narrow band wireless communication systems, UWB has a bright future in Wireless Personal Area Network ,and has became one of the most competitive and promising technologies in the near future. Application of UWB networks is getting wider and wider and research on UWB networks has already become one important direction in wireless communication technology.Security is a critical issue for potential application of UWB networks. At present, it does not generally start researching the security of UWB Networks, but, obviously, it is very important and urgent to research the security of UWB Networks .Therefore, in this thesis, the secure research on UWB Networks is completely based on UWB ECMA-368 standard made by WiMedia. But providing security in UWB networks is challenging due to all the characteristics of these networks, such as the vulnerability of the wireless links; the limited physical protection of each node or the dynamically changing topology. Attacks against UWB networks, such as DoS attacks, Modes of Operation, Multicast and node Intrusion Detection, all of them prevent application of UWB technology. It is very essential to resolve these attacks.In this dissertation, we investigate a series of security problems in UWB networks. Our contribution mainly includes four parts. Main contents and innovation points in this dissertation are as follows:1)On UWB networks attacks and defending:Owing to UWB networks based on UWB ECMA-368 standard is a open and distributed network without center control, the probability of being attacked by DoS attack will increase greatly. There is not any special secure mechanism avoiding DoS attack in ECM368. Although by seting MKID and saving least information in 4-way handwork to decrease the probability of UWB networks being attacked by DoS attack, there are still some secure weakness in UWB networks. In UWB networks, Denial of Service(DoS) mainly exists in MAC and network layer. Considering the characters of DoS in MAC of UWB networks, a defensive system combining characteristic detection and anomaly detection is proposed in this thesis. Furthermore, the detecting algorithm in this scheme are described. Finally, the performances of the detection system in both false alarm and memory expense by simulation are analyzed, the testing result showes that this scheme presented in this paper has a good performance .Attacks occurred in UWB network layer are also called routing attack. UWB flooding attack based on DATA is researched in this thesis. Then, the detection method based on routing deletion is presented in this paper to prevent the aboved attck. The novelly research on UWB networks attacks and defending has great value for protect the security of UWB networks at UWB MAC layer and UWB network layer from the DoS attack.2)On research on modes of operation in UWB networks:Due to the slow speed of CBC-MAC mode which is the main demerit in UWB networks, we improve on it and propose a fast and secure operation mode of block cipher. This new mode has distinct speed advantage over the standard mode CCM(CTR with CBC-MAC) and are superior to the CCM mode in whole performances.3)On research on multicast communication security in UWB MAC layer:How to control the enter/leaving of group member and the generation,issuance and update of group key is the key of multicast secure management. In UWB standand, MAC layer secure multicast updates group key only in the special case , without considering some series of questions of spending and security after update of group key and solution on these questions. Therefore, there are some secure weakness in UWB multicast secure prevention and protection ability, which are important factors of limiting UWB technology development and application in the environment of many UWB user. In this dissertation, a method of multicast key management in UWB MAC layer based on one-way function tree architecture is firstly presented. This method adds the function modules of multicast key management on the center of tree architecture based on the extension of UWB 4-way handwork , to constitute the secure system of UWB multicast. Experimental results demonstrate that the merits of this method are as flows: 1) decreasing the corresponding spending of multicast key update; 2) decreasing the delay of multicast key update; 3) providing authentication function for multicast key update frame; 4) increasing the dependability of multicast key update; 5) increasing the flexibility of multicast. Therefore, this scheme can greatly increase the security of multicast communication in UWB networks, furthermore, has little influence on present UWB standard due to the flexibility of architecture.4)On research on node intrusion detection in UWB networks:Because of these characters , for example, wireless channel anddynamic topology in UWB networks, baleful node can easily disguiseidentity to enter UWB networks, even legal node maybe enter UWBnetworks after being captured. Hence, intrusion detection is also an importand secure method except for the identity authentication on node. In this paper, a novelly distributed in-trusion detection system based on clusters and mobile agents is put forward for UWB Networks. In this intrusion detection system, in order to saving the limited resources and network bands, nodes use distributed algorithm to collect data and detect network's behavior. At the same time, the system also can detect host computer' behavior and network's behavior. Furthernore, since the nodes of cluster head can synthetically analysis the alarming information offered by other nodes, this intrusion detection system can detect attacks at different layers in UWB Networks. Finally, a fast intrusion detection algorithm applying UWB networks is put forward by research on node intrusion detection mechanism in UWB networks. This algorithm is based on finite state automaton(AC algorithm) combined with Boyer-Moore(BM) algorithm and an improved Quick Search(QS) algorithm. In general, the algorithm described does not need to test each character in the string. By making full use of the results of matching successes and failures, the algorithm can often bypass inspection of as many characters as possible and get all matching locations after one quick search. Experimental results demonstrate that the proposed algorithm achieves excellent performance in the cases of both short patterns and long patterns and effectively improve the performance of keyword detection and filtering.