Research On Secure Communication Technologies In Wireless Mesh Networks

Wireless Mesh Networks (WMN) is a kind of self-organizing and self-configuringnetwork. WMN is an expansion and extension of Internet in wireless area. It containsnot only the characteristics of wireless networks but also multi-hop, self-organizing,self-configuring, and so on. Each node in a WMN may be attacked directly orindirectly by malicious attackers, because WMN lacks a definite network defenseborder. So, it's very difficult to ensure the security of communications in WMN. Withincreasing applications of WMN, how to guarantee communication security hasbecame a crisis problem, and it should be solved appropriately.To slove above topics, this dissertation focuses on securing communication inWMN. It concludes and analyses the present status and future challenges of securecommunication issues in WMN. On the basis of the traditional network securitymechanisms and the inherent characteristics of WMN, novel researches onguaranteeing communication secutity in WMN are explored without adding anyhardware. The main works are as follows:(1) Secure communication architecture of WMN is studied in detail. A novelMulti-path based Secure Communication (MSC) is proposed. It is used toprovide secure communications in WMN.(2) Technologies of detecting link-disjoint (or node-disjoint) multiple paths arestudied in detail. A novel EDSR algorithm is proposed to provide link-disjoint(or node-disjoint) multiple paths for network nodes in WMN. It's animprovement of the DSR route protocol.(3) Secure key exchange algorithms are studied in detail. Novel key exchangemethods are proposed to distribute session keys effectively for communicationnodes through multiple paths or single path in WMN.(4) Trust evaluation mechanisms are studied in detail. A novel trust model isproposed according to the minimal principle of uncertainty metric. The model is used to evaluate the trust values of nodes and helps network nodes to chooseproper routes in WMN.(5) Incentive mechanisms in WMN are studied. The proposed new mechanismmakes network nodes act as normal by deploying limited rational game amongall of network nodes.(6) Technologies of network communication abnormal monitoring are studied inWMN. The proposed new monitor is built on middleware technology. It isused to maintain and monitor abnormal cases of the network.MSC deploys the limited rational game based incentive mechanism in wholenetwork, and makes nodes act as normal. When a node needs to send packets toanother node, it will use the detection algorithm to find link-disjoint (or node-disjoint)multiple paths. Then it chooses proper paths according to the evaluation results ofproposed trust model, which is based on the minimal uncertainty metric. At last, MSCuses of the key exchange methods to distribute session keys for communication pairs.And these keys are used to encrypt data and enhance the security of communications.Additionally, MSC uses of agent based network communication abnormal monitoringmechanism to maintain and monitor abnormal cases of the network. Simulation resultsindicate that the proposed MSC mechanism can improve the reliability and decreasethe security risk of communications effectively.