Vehicular ad hoc networks (VANETs) have drawn increasing attention in recent years due to their wide range of applications. At the present time, vehicle communication is exposed to many security threats, such as denial of service (DoS) attacks. In these attacks, a malicious node forges a large number of fake identities. Internet Protocol (IP) spoofing addresses is to disrupt the proper functioning of the fair data transfer between two fast moving vehicles. In this paper, IP spoofing addresses of DoS attacks have been detected and defended by using the Bloom-filter based IP-CHOCK detection method, which provides the availability of a service for the legitimate vehicles in the VANET. The IP spoofing addresses in the DoS attacks committed by fraud and malicious nodes have also been investigated. This method provides a secure communication as well as frees the bandwidth. This proposed approach requires fewer resources and is easy to deploy. Simulation results have shown that this method is efficient and effective to detect and defend against DoS attacks in the VANET. Specifically, this method provides faster detection time, lower storage capacity, and computational cost. © 2014 John Wiley & Sons, Ltd.