الخلاصة

Mobile ad hoc networks (MANET) is a type of networks that consists of autonomous nodes connecting directly without a top-down network architecture or central controller. Absence of base stations in MANET force the nodes to rely on their adjacent nodes in transmitting messages. The dynamic nature of MANET makes the relationship between nodes untrusted due to mobility of nodes. A malicious node may start denial of service attack at network layer to discard the packets instead of forwarding them to destination which is known as black hole attack. In this paper a secure and trust based approach based on ad hoc on demand distance vector (STAODV) has been proposed to improve the security of AODV routing protocol. The approach isolates the malicious nodes that try to attack the network depending on their previous information. A trust level is attached to each participating node to detect the level of trust of that node. Each incoming packet will be examined to prevent the black hole attack. .