Biblio

A mobile ad hoc network (MANET) is vulnerable to many types of attacks. Thus, security has turned out to be an important factor to facilitate secured communication between mobile nodes in a wireless environment. In this paper we propose a new approach to provide reliable and secure data transmission in MANETs under possible blackhole attacks based on ad hoc on-demand multipath distance vector (AOMDV) protocol and homomorphic encryption scheme for security. The performance of the proposed scheme is stable but that of AOMDV is found to be degrading with the intrusion of malicious nodes in the network. Simulation results show the improvement of packet delivery ratio and network throughput in the presence of blackhole nodes in our proposed scheme.

The performance of ad hoc networks depends on the cooperative and trust nature of the distributed nodes. To enhance security in ad hoc networks, it is important to evaluate the trustworthiness of other nodes without central authorities. An information-theoretic framework is presented, to quantitatively measure trust and build a novel trust model (FAPtrust) with multiple trust decision factors. These decision factors are incorporated to reflect trust relationship's complexity and uncertainty in various angles. The weight of these factors is set up using fuzzy analytic hierarchy process theory based on entropy weight method, which makes the model has a better rationality. Moreover, the fuzzy logic rules prediction mechanism is adopted to update a node's trust for future decision-making. As an application of this model, a novel reactive trust-based multicast routing protocol is proposed. This new trusted protocol provides a flexible and feasible approach in routing decision-making, taking into account both the trust constraint and the malicious node detection in multi-agent systems. Comprehensive experiments have been conducted to evaluate the efficiency of trust model and multicast trust enhancement in the improvement of network interaction quality, trust dynamic adaptability, malicious node identification, attack resistance and enhancements of system's security.