Improving Security Issues in MANET AODV Routing Protocol

Mobile Ad-hoc Networks ( MANETs) are forming dynamically by joining or leaving the nodes into/ from the network without any fix infrastructure. It is also possible that each mobile node act as a host or router. This kind of wireless network is prone to various security threats or attacks due to its unique characteristics like dynamic topology, open medium, lack of central monitoring, etc. So security is a vital scope in MANET to protect communication between mobile nodes. Ad-hoc On-demand Distance Vector ( AODV) is one of the on-demand reactive routing protocols in MANET that initially was improved without considering security protection. Significant attempts have been done to secure AODV routing protocol in MANET but there are still critical challenges to overcome. In the present study, after reviewing secured protocols of some previous researches, an improved protocol is proposed to enhance the security of AODV routing protocol against black hole attack. For this purpose, we used a different level of trust for MANET nodes and imposed the limitations based on the nodes' trust level, in order to detect the compromised nodes and malicious behaviors inside MANET; which leads to the low delay and high performance in the network. Finally, we simulated the proposed protocol with NS-2 simulator as a means to validate it and evaluate the results. In fact, the results, demonstrate the efficiency of the presented protocol and its resistance to the black hole attack in comparison to AODV routing protocol.