A Consensus-based Trust Management Model In MANET

The mobile ad hoc network(MANET)has the advantages of not being restricted by fixed network facilities,fast,flexible,and adaptable.It is widely used in military communications,emergency rescue,field-working,and social daily life.With the increasing number of malicious nodes and malicious behaviors in the network,how to ensure the network security and availability has been an important research topic in recent years,especially for mobile ad hoc networks due to its inherent nature of peers' strong mobility and short wireless transmission range.Usually,the trust models are employed in MANET for guaranteeing the transactions' success,where the peers' mobility is handled by either periodically broadcasting Hello messages or constructing multi-layered network structure.However,such trust models would largely increase the communication complexity.In this paper,we proposes a MANET trust management model based on a lightweight consensus algorithm,named LocTrust.The consensus mechanism plays an irreplaceable role in ensuring the consistency and availability in distributed systems.In addition,the consensus mechanism can also be applied to the scenarios of establishing mutual trust among nodes in a distributed system.This brings new ideas to the research of MANET trust management model.The LocTrust model provides MANET nodes a complete solution for selecting credible resource providers to interact with,and greatly improves network availability while ensuring security.The main challenge of applying the consensus mechanism to mobile ad hoc networks is how to reduce the computational complexity and communication complexity brought by the consensus algorithm itself to reduce the burden on mobile peers.Therefore,in order to reduce the complexity of communication,this model proposes two consensus algorithms,the local trust consensus algorithm and the global trust consensus algorithm,for transactions established between nodes in the same sub-net and transactions established between nodes coming from different sub-nets.This avoids the unnecessary waste of bandwidth and computing power caused by the frequent implementation of the consensus mechanism within the entire network.Meanwhile,this paper builds a two-layer network architecture based on super nodes as the network structure of the LocTrust model.Super nodes are elected to manage members of the sub-net and proxy members in the sub-net to participate in the global trust consensus process,which improves security performance and reduces the communication complexity of the consensus algorithm.Finally,through research and analysis,for MANET with limited resources,we define trust as five levels in the consensus algorithm.This can greatly reduce the computational complexity of the algorithm and further improve the availability of the LocTrust model.The simulation results show that the trust model we proposed in this paper could both improve the resource search success rate and reduce the communication complexity.