Research Of Trusted Secure Routing Techniques In Mobile Ad Hoc Networks

As an important component of the fourth generation network, mobile ad hoc networks have great martial value and wide applications. The unique characteristics of mobile ad hoc networks, such as open wireless channel, infrastructureless, striengent resource constraints, and fully distributed architecture, pose a number of vulnerabilities. Secure routing is one of the fundamental security problems in mobile ad hoc networks.Until now, there are still many secure routing problems to be solved: applicability due to lack of the consideration on the characteristics of application scenarios; incomplete schemes that are lack of systematic view; scalability; lack of considerations for soft security such as trust.There are three essential issues in the research of MANET secure routing technology: First, tradeoff between overhead and performance; Second, establishing trust among nodes in MANETs; Third, considerations for specific requirements of different application scenarios. We carry out our research in addressing the above-mentioned issues.Cryptography mechanism is the basis of secure routing protocols. We propose a bilinear pairing based key agreement scheme that uses of the forefront work in cryptography such as elliptic curve cryptography and bilinear pairing theory through the analysis of cryptography mechanisms taken by existing mobile ad hoc network secure routing protocols. Our proposed scheme distinguishes neighbor authentication process for getting access to network and remote key agreement for confident data transmission. Neighbor authentication process is simplified to reduce computing and communication overhead without prejudicing the integral safety. This scheme is very suited to mobile ad hoc network for short key length, quick computing speed, small amount of data.Mobile ad hoc networks with high level security have special requirement for anonymity which has been investigated extensively in wired networks. But the anonymity solutions in wired networks which need the support of infrastructure are not suitable for mobile ad hoc networks that are infrastructureless and resource-constrained. We propose an anonymous trust based secure routing protocol which is called ATR for such application scenarios. Firstly, a bilinear pairing based key agreement scheme is designed to achieve identification anonymity through multi-pseudonyms. Link pseudonyms are also negotiated by neighbor authentication process. On the basis of proposed key agreement scheme, we propose a virtual label switching protocol to achieve relationship anonymity by incorporating the basic idea of Multi-Protocol Label Switch (MPLS). Then we design our anonymous trust based secure routing protocol on the basis of above work. Simulation results have shown that our scheme does a very good job at anonymity to prevent traffic analysis attack through identification anonymity and data untraceability with 10% performance degradation.Node and link failure introduced by routing attacks are important factors that threaten the survivability of mobile ad hoc networks. Protecting the integrality of routing messages is just the initial step to ensure network connectivity. Inside attackers may correctly participate in route discovery process but fail to correctly forward packets, which would bring the loss of critical data that is important for command and control in tactical radio network. So we propose a trust based survival secure routing protocol aiming at the problems. In our proposal, multi-paths with trust evaluation for each hop are returned in route discovery phase. The source node then evaluates the trust degree of established paths according to hop-by-hop trust calculation. Trust value for different paths is updated on the basis of data transmission results. Simulation results show that our trust-based survival secure routing protocol presents good performance in hostile environments.The two schemes stated above need the deployment of cryptographic mechanism. But nodes in some mobile ad hoc networks have very constrained computing capability and energy, and such networks normally do not need high-level routing security. Therefore, we propose a light-weight cross-layer secure routing protocol which does not need cryptographic mechanism to satisfy the requirement of mobile ad hoc networks with low-level security. Simulations show that our light-weight cross-layer secure routing protocol can ensure some degree of routing security in a limited hostile environment.This thesis proposed three secure routing protocols according to different application scenarios to satisfy different requirement. We hope that our work will benefit future research on secure routing in mobile ad hoc networks.