# Efficient Secure Mechanisms for In-Vehicle Ethernet in Autonomous Vehicles
###### Abstract  
The integration of external devices and network connectivity into autonomous vehicles has raised significant concerns about in-vehicle security vulnerabilities. Existing security mechanisms for in-vehicle bus systems, which mainly rely on appending authentication codes and data encryption, have been extensively studied in the context of CAN and CAN-FD buses. However, these approaches are not directly applicable to Ethernet buses due to the much higher data transmission rates of Ethernet buses compared to other buses. The real-time encryption and decryption required by Ethernet buses cannot be achieved with conventional methods, necessitating an acceleration in the speed of cryptographic operations to match the demands of Ethernet communication. In response to these challenges, our paper introduces a range of cryptographic solutions specifically designed for in-vehicle Ethernet networks. We employ an AES-ECC hybrid algorithm for critical vehicle control signals, combining the efficiency of AES with the security of ECC. For multimedia signals, we propose an improved AES-128 (IAES-128) and an improved MD5 (IMD), which improve encryption time by 15.77%. Our proposed security mechanisms have been rigorously tested through attack simulations on the CANoe (version 10) platform. These tests cover both in-vehicle control signals, such as braking and throttle control, and non-critical systems like multimedia entertainment. The experimental results convincingly demonstrate that our optimized algorithms and security mechanisms ensure the secure and reliable operation of real-time communication in autonomous vehicles. automous vehicles; Ethernet; security mechanism; in-vehicle control signals; multimedia signals +
Footnote †: journal: Electronics* Body Control Unit (BCU): Manages vehicle body electronics, such as window controls and door locks, enhancing comfort and convenience. It includes various ECUs such as the Local Control Unit (LCU), System Control Unit (SCU), Sensor Region Control Unit (SRCU), and Microcontroller Unit (MCU). * Powertrain Control Unit (PCU): Oversees the vehicle's power output and transmission efficiency, which is crucial for performance and fuel economy. This unit integrates components like the Domain Gateway, Engine Management System (EMS), and Transmission Control Unit (TCU). * Chassis Control Unit: This unit manages vehicle stability and control, including the Electronic Stability Control (ESC) Unit and Power Control Unit (PCU), which are vital for maintaining vehicle dynamics and energy management. * Infotainment System: This system provides entertainment and connectivity features within the vehicle. It includes components like multimedia interfaces, navigation systems, and communication modules that enhance the in-car experience for passengers and drivers. However, this technological advancement also introduces new security challenges, especially for mission-critical vehicle operations such as braking and acceleration. These operations are particularly vulnerable to cyberattacks, including cross-VLAN and denial-of-service attacks, which can lead to significant safety hazards [3]. Autonomous vehicles leverage multi-network convergence technology to achieve a wide range of in-vehicle functionalities. However, this also results in an increased number of interfaces for accessing the vehicle's internal and external networks. Unfortunately, these interfaces can serve as potential entry points for malicious attacks [3]. For instance, when the in-vehicle electronic control system is connected to external network systems like WiFi, Bluetooth, OBD (On-Board Diagnostics) II network testers, and cellular networks, hackers may exploit these connections to steal information from the in-vehicle bus network. Subsequently, they could potentially invade the in-vehicle Ethernet system via remote control, thereby tampering with the in-vehicle control signals of vital components such as the engine, throttle, brakes, and steering wheel [4].