Recent technical innovation has driven the evolution of autonomous vehicles. To improve safety as well as on-road vehicular experience, vehicles should be connected with each other or to vehicular networks. Some specification groups, e.g., IEEE and 3GPP, have studied and released vehicular communication requirements and architecture. IEEE’s Wireless Access in Vehicular Environment focuses on dedicated and short-range communication, while 3GPP’s New Radio V2X supports not only sidelink but also uplink communication. The 3GPP Release 16, which supports 5G New Radio, offers evolved functionalities such as network slice, Network Function Virtualization, and Software-Defined Networking. In this paper, we define and design a vehicular network architecture compliant with 5G core networks to enable and support autonomous driving. As a validation example, a high-definition map needs to contain the context of trajectory for localization and planning of autonomous driving vehicles. We also propose new methods by which autonomous vehicles can push and pull map content efficiently, without causing bottlenecks on the network core. We evaluate the performance of the proposed method via network simulations and our autonomous driving vehicle on the road. Experimental results indicate that the proposed method improves the performance of vehicular content delivery in real-world road environments.

As vehicular technology matures, various monitoring devices that are operational, even when the vehicle is parked, are being developed and installed. When the vehicular ad-hoc network (VANET) is commercialized, it is expected that these devices will be able to transmit the data collected to other vehicles or the owner of a vehicle, wirelessly. To accomplish this, group communication can be employed for security and efficiency. However, if a vehicle is parked out of communication range of a roadside unit (RSU) when a group key is modified, it cannot participate in the group communication. Moreover, even when the parked vehicle has the latest group key, transmitting large amounts of data remains problematic. In this paper, we propose solutions that enable vehicles parked out of the communication range of RSU to participate in group communication. First, we provide a running-vehicle-to-parked-vehicle group key transmission scheme. Second, we develop a scheme for transmitting large files. Using these two schemes, the parked vehicle can not only participate in group communication when the group key is changed, but also transmit large amounts of data, such as a blackbox clips, to the owner of a vehicle or other passing vehicles. In security analysis, we prove that the proposed scheme is protected from common attack scenarios.

Group key management (GKM) in mobile communication is important to enable access control for a group of users. A major issue in GKM is how to minimize the communication cost for group rekeying. To design the optimal GKM, researchers have assumed that all group members have the same leaving probabilities and that the tree is balanced and complete to simplify analysis. In the real mobile computing environment, however, these assumptions are impractical and may lead to a large gap between the impractical analysis and the measurement in real-life situations, thus allowing for GKM schemes to incorporate only a specific number of users. In this paper, we propose a new GKM framework supporting more general cases that do not require these assumptions. Our framework consists of two algorithms: one for initial construction of a basic key-tree and another for optimizing the key-tree after membership changes. The first algorithm enables the framework to generate an optimal key-tree that reflects the characteristics of users’ leaving probabilities, and the second algorithm allows continual maintenance of communication with less overhead in group rekeying. Through simulations, we show that our GKM framework outperforms the previous one which is known to be the best balanced and complete structure.

With the emergence of diverse group-based services, multiple multicast groups are likely to coexist in a single network, and users may subscribe to multiple groups simultaneously. However, the existing group key management (GKM) schemes, aiming to secure communication within a single group, are not suitable in multiple multicast group environments because of inefficient use of keys, and much larger rekeying overheads. In this paper, we propose a new GKM scheme for multiple multicast groups, called the master-key-encryption-based multiple group key management (MKE-MGKM) scheme. The MKE-MGKM scheme exploits asymmetric keys, i.e., a master key and multiple slave keys, which are generated from the proposed master key encryption (MKE) algorithm and is used for efficient distribution of the group key. It alleviates the rekeying overhead by using the asymmetry of the master and slave keys, i.e., even if one of the slave keys is updated, the remaining ones can still be unchanged by modifying only the master key. Through numerical analysis and simulations, it is shown that the MKE-MGKM scheme can reduce the storage overhead of a key distribution center (KDC) by 75 percent and the storage overhead of a user by up to 85 percent, and 60 percent of the communication overhead at most, compared to the existing schemes.

A logical key hierarchy (LKH) based key managementapproach is the most common way to manage a group keywith less rekeying overhead. However, the LKH approach causes inefficiency of rekeying the group key in mobile cellular networks since it does not consider the characteristics of the networks, such as the cell-based network topology and the user's mobility. This paper proposes an efficient and practical group key management scheme dedicated to the mobile cellular networks. This new approach can achieve better performance with less management overhead than other currently available schemes, by the cell-based decentralization of key management functions. Through comparisons with other possible approaches, it is shown that the proposed scheme can obtain much better performance in terms of the communication overhead.

The integration of a driving simulator and an unmanned vehicle by means of a performance concept is suggested. Autonomous navigation is one of the most difficult research topics, having constraints on mobility and speed, and lack of environmental information. However, many innovations on the vehicle provide the appropriate automatic control in vehicle subsystem for reducing human error. The master system has a host computer and simulator and the slave system is electronic vehicle system. The slave vehicle system consists of three parts. First, laser sensor system for keeping the front sensory system and ultrasonic sensor system for escaping collision at the side. Second, acceleration system and brake control system for longitudinal motion control. Third, steering control system for lateral motion control. In this research, mechanical and electronic parts are implemented to operate unmanned vehicle as a whole-integrated system. Driving simulator has a 6 degree-of-freedom motion-base and 3-channel fixed-based simulator. They are fully interactive, highly realistic and, based on personal computer, can be updated easily. Driving simulator is constituted by a vision system, a sound system, the system for control force loading and the 6-axis Stewart platform for motion base. This paper focuses on the integration of remote controlled unmanned vehicle and driving simulator. The vehicle mainly controlled lateral direction and longitudinal direction with actuators for controlling vehicle movement and sensors for closed-loop system.