AADHOC: An adaptive realtime distributed MAC protocol for Vehicular Ad Hoc Networks Vehicular Ad Hoc Networks (VANET) is the foundation of Intelligent Traffic System (ITS), and recently many MAC protocols for VANET are proposed, among which a reliable MAC protocol called ADHOC has aroused much attention. By investigating the details of ADHOC protocol, we have discovered several unsolved problems that might lead to a network failure. In this paper, we provide a quantitative analysis of the success probability for contending nodes and prove that an adaptive frame length is quite necessary. We propose AdaptiveADHOC (AADHOC) MAC protocol, which implements a robust mechanism supporting the adaptive frame length. Evaluation result shows that AADHOC can maintain a high contending success probability and obtain about 50% reduction of response time over original ADHOC protocol, while providing important enhancement on network robustness.

An enhanced anonymity resilience security protocol for vehicular adhoc network with Scyther simulation Abstract   Vehicular AdHoc Network (VANET) refers to the wireless interconnection of vehicles for exchanging useful information among them. The transmitted information provides insight into safety and comfort in driving. It is also used in the analysis of traffic, road safety measures, vehicle performance data, and multimedia data transfer between vehicles using uninterrupted Internet connectivity. Adversaries can create several interruptions in the system after extracting sensitive information. Hence, a robust security protocol is essential to establish secure communication. In this article, we investigate the Bidi etxc2xa0al.xe2x80x99s protocol and find that the protocol has several important security flaws. We then propose a robust protocol that guarantees highlevel security protection on the existing security attacks and additionally, protects all related possible attacks. Furthermore, our simulation using Scyther confirms that all the private information is protected during establishing a common key. All the performance factors of the protocol are also superior in comparison with existing works.