Secure & Efficient Routing Mechanisms in VANET Using CBDS

Vehicular Adhoc Network (VANET) is adhoc network. In VANET topology is changing continuously due to the dynamic nature of the vehicles. Due to the open nature of VANET, It is vulnerable to black hole attack, Gray hole attacks, etc. In black hole attack malicious node that immediately replies to route requests by source nodes without having an active route to a specified destination and drop all the receiving data packets. The attack may cause major damage if two or more black hole nodes cooperate with each other to launch an attack. A novel Secure Routing mechanism With Hybrid Defense for mitigating collaborative black hole attacks and gray hole attacks in VANETs, referred to as `Co-operative Bait Detection Scheme'. It is a combination of Both Proactive & Reactive detection strategies. The CBDS scheme uses Reverse tracing technique to identify the malicious nodes. At a later stage, if the destination node detects a significant loss in data packets, the initial intrusion detection mechanism will be triggered again to identify malicious nodes. Proactive detection in CBDS scheme Consist of Two steps such as Initial Bait Phase and Reverse Tracing Step. Reactive Detection of proposed scheme uses a dynamic threshold algorithm to detect variants of black hole attacks.