## 1 Introduction  
The rapid growth in the global human population has resulted in a substantial increase in the number of vehicles on the roads. In today's world, private vehicles are the predominant mode of transportation, leading to an intensified strain on transportation infrastructure and safety. This surge in vehicle usage has consequently caused a rise in traffic accidents, highlighting the urgent need for safer and more efficient transportation solutions [1]. To alleviate range anxiety in electric vehicles, ensure safe and comfortable travel,and implement coordinated, mobility-aware charging strategies, there is a continuously growing demand for Intelligent Transportation Systems (ITS). These systems facilitate the exchange of critical information, such as traffic conditions, accidents, emergencies, and roadworks, among drivers. As a result, ITS enhances traffic flow management, enables early detection of potential hazards, and helps to mitigate the risk of accidents [2]. Initially, Mobile Ad Hoc Network (MANET) technology was used for wireless communication between vehicles, but due to its inability to meet the security and specific application requirements, it was replaced by Vehicular Ad Hoc Networks (VANETs). VANETs are critical in supporting autonomous driving, enhancing road safety, optimizing traffic flow, and improving passenger experience. VANETs facilitate vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to-pedestrian (V2P) communications, sharing information about road conditions, traffic density, and incident notifications to provide a safer and more efficient driving experience [3]. However, the traditional VANET architecture is insufficient to meet the basic requirements of intelligent transportation systems regarding network management, scalability, and routing. The existing VANET architecture, especially with the advent of 5G technology, is inadequate for content-based information sharing. Therefore, new network architectures are required to meet the needs of smart cities and intelligent vehicle technologies [4]. The Software Defined Networking (SDN) paradigm offers effective solutions to the scalability and management challenges of traditional VANET architectures. By decoupling the control and data planes, SDN enables centralized management of the network by a controller, allowing VANET networks to be managed more efficiently and effectively [5]. This centralized control and flexibility help overcome the scalability and coordination issues of traditional VANETs. The benefits of SDN play a significant role in the future of intelligent transportation systems through a new architecture known as SD-VANET (Software Defined-based Vehicular Ad Hoc Networks) [6]. In addition, SDN technology optimizes energy management for electric vehicles, increases the efficiency of charging infrastructure, supports vehicle-to-grid (V2G) integration, and enables dynamic pricing mechanisms. SDN also improves security by protecting the charging infrastructure from cyber threats [7]. In this context, SDN is emerging as a critical component in making the energy demands and grid support of electric vehicles more efficient. Although SD-VANET has the potential to revolutionize intelligent transportation systems, it is vulnerable to cyberattacks like any other system. In particular, Distributed Denial of Service (DDoS) attacks pose a serious threat to SD-VANETs. Such attacks target the centralized controller of the SD-VANET, and a successful attack on the controller can adversely affect the entire network, resulting in degraded network performance or complete communication failure [8]. This situation threatens traffic safety, making the security of SD-VANETs critical to the success of intelligent transportation systems. Therefore, cybersecurity should be prioritized in designing these systems, and anomaly traffic detection systems must be developed to counter threats such as DDoS attacks [9].