Design of an intelligent protocol for security challenges in mobile ad-hoc network

Abstract

The security issues are more complex and challenging in Mobile Ad hoc Networks (MANETs) than other conventional wireless networks due to peer to peer behavior of the participating nodes, absence of centralized routers and routing through intermediate nodes. For successful communication between a pair of source and destination it is vital that the intermediate nodes be trustworthy and don t drop packets. Nodes in an ad hoc network may not be trustworthy either due to selfishness created by power loss or due to maliciousness relating to rogue intentions. A node that was earlier trust worthy may no longer be so at later stages due to loss of power making the continuous dynamic evaluation of trust a necessity. Also the security requirements may vary as per the conditions on the scenario. This thesis proposes an intelligent protocol that takes care of both selfishness and maliciousness. The protocol provides a kick start to the system on the initial basis for the purpose of trust worthiness, evaluates the trust dynamically, takes into consideration the trust worthiness of the node supplying the second hand trust information and is able to adapt to various levels of security requirements. The proposed protocol is able to overcome the basic drawbacks of conventional trust based systems such as it takes time for the trust index to grow to a requisite level before a node can be selected as the intermediate node with confidence, it is quite possible that a node which was earlier trustworthy may no longer be so as it may become selfish due to its energy loss with the passage of time, a node supplying the second hand trust information may itself be not reliable and the threshold trust index requirement may be different for the different application scenarios. newlineThe proposed protocol is a modification of basic AODV protocol and has been named as AODV-n. The value of n can be 0,1,2,3 depending upon the security level requirements, 0 being the least secure and 3 being the most secure one.