## 2 State of the Art
### Use of the Internet of Vehicles (IoV) in Vehicle Logistics  
The Internet of Vehicles (IoV) is an extension of the Internet of Things (IoT) that connects vehicles, infrastructure, and devices through smart grids to facilitate real-time communication. In the field of vehicle logistics, this technology has transformed the way operations are managed, enabling a constant flow of data that improves the efficiency, safety, and sustainability of transportation [13]. Its impact is particularly relevant in Ro-Ro terminals, where dynamic vehicular traffic management is critical due to the volume and frequency of operations. In Ro-Ro terminals, the IoV enables intelligent vehicular traffic management, optimizing internal routes and minimizing waiting times. Through V2X (vehicle-to-everything) technology, vehicles can communicate directly with port infrastructures (V2I) and with other vehicles (V2V), sharing information such as estimated time of arrival, internal route conditions, and dock assignments. This allows operations to be adjusted in real time, improving coordination between vehicles and reducing congestion in key areas [14]. A key aspect of the IoV in this context is its ability to support advanced space and time allocation systems. For example, the use of predictive algorithms integrated with real-time data makes it possible to optimize the parking and loading of vehicles on ships, reducing operational times and maximizing the use of terminal capacity [15]. These improvements also contribute to greater operational sustainability by reducing fuel consumption and greenhouse gas emissions associated with long wait times. In addition, the IoV makes it easy to implement driver-assistance technologies such as collision warning systems and adaptive cruise control. These technologies not only improve operational safety, but also reduce the risk of damage to vehicles and port infrastructure, a recurring problem in terminals with high traffic density [16]. Despite its benefits, the implementation of the IoV in port terminals faces significant challenges. The lack of advanced technological infrastructure, such as 5G communication networks, limits the ability of IoV systems to handle large volumes of data in real-time. In addition, resistance to change in traditional operational processes and the need for specialized training for operators and drivers also delay their adoption [17]. Interoperability between different IoT systems and technological standardization are critical issues that need to be addressed to ensure widespread adoption in the port sector. Across Europe, the adoption of IoV and blockchain technologies is reshaping port operations, with many countries investing heavily in digital transformation. Ports such as Rotterdam in the Netherlands, Antwerp in Belgium, and Hamburg in Germany have implemented IoV systems to enhance real-time communication between transport modes and port infrastructure. These initiatives have enabled the efficient coordination of vehicle flows, reduced turnaround times, and minimized environmental impacts. In addition to IoV, blockchain is being used to secure data exchange, streamline customs procedures, and ensure traceability of goods across the supply chain. Ref. [18] highlights that European ports,especially those involved in multimodal logistics, are at the forefront of adopting space-efficient and digitally integrated solutions. For example, the Port of Antwerp's blockchain pilot projects have demonstrated the potential for secure, real-time cargo documentation, which aligns with the EU's broader goals for digitalization and sustainability. These advancements place European ports in a leadership position, demonstrating how technology can address challenges such as congestion, inefficiency, and environmental impact. In the case of Spain, the implementation of IoV in port terminals could position these ports as leaders in logistics innovation in Europa.