| dc.description.abstract | A mobile Ad hoc network (MANET) is a wireless decentralized self-configuring network in which nodes communicate with each other either directly or through intermediate nodes. These unique features (self-configuring, infrastructure-less, decentralized) make MANET suitable for use in emergency situations, military operations, education, entertainment, sensor networks etc. Besides the various advantages, the open medium, rapidly changing topology and lack of centralized monitoring make MANETs vulnerable to various attacks. This dissertation work focuses on network layer attacks. Network layer attacks in MANET are categorized into two basic types namely active and passive. In active attack, an attacker disrupts the regular operation of the network, change the data or harm the system. In passive attack, the attacker does not disturb the operation of network but attempts to seek some valuable information. So, it is vital to develop some security mechanism to protect MANETs from attacks. This dissertation work focuses on providing solution to prevent MANETs from two active attacks namely Blackhole and Malicious Packet Dropping and one passive attack namely Eavesdroping attack.
The existing AODV Protocol is modified to prevent these attacks. Solution is proposed and simulated to prevent Blackhole and Eavesdropping attack. Malicious packet dropping attack is prevented by using Watchdog Intrusion Detection System (IDS). Performance of AODV and Modified AODV protocol is analysed with respect to Packet Delivery Ratio, Average End-to-End Delay and Routing Overhead. To prevent Eavesdropping attack, a hybrid cryptography technique has been developed which combines best features of both symmetric key cryptography and asymmetric key cryptography i.e. speed and security. Simulation has been done in Network Simulator version 2.35. | en_US |
