QoS Assertion in MANET Routing based on Trusted AODV (ST-AODV)

Mobile ad hoc network is a standalone network capable of autonomous operation where nodes communicate with each other without the need of any existing infrastructure. They are self configuring, autonomous, quickly deployable and operate without infrastructure. Mobile ad hoc networks consist of nodes that cooperate to provide connectivity and are free to move and organize randomly. Every node isrouter or an end host, in general autonomous and should be capable of routing traffic as destination nodes sometimes might be out of range. Nodes are mobile since topology is very dynamic and they have limited energy and computing resources. These nodes are often vulnerable to failure thus making mobile ad hoc networks open to threats and attacks. Communication in MANET relies on mutual trust between the participating nodes but the features of MANET make this hard. Nodes sometimes fail to transmit andstart dropping packets during the transmission. Such nodes are responsible for untrustworthy routing. A trust based scheme can be used to track these untrustworthy nodes and isolate them from routing, thus provide trustworthiness. In this paper a trusted AODV (ST-AODV) protocol is presented which assigns a trust value for each node. Nodes are allowed to participate in routing based on their trust values. A threshold value is assigned and if the nodes trust value is greater than this value its marked as trustworthy node and allowed to participate in routing else the node is marked untrustworthy. The STAODV increases PDR and decreases delay thereby enhancing the QoS metrics and trustworthiness in AODV based MANET routing. The work is implemented and simulated on NS-2. The simulation result shows the proposed ST-AODV provides more trustworthy routing compared with general AODV in presence of packet dropping nodes in MANET.