# Efficient Secure Mechanisms for In-Vehicle Ethernet in Autonomous Vehicles
###### Abstract
Consequently, during data transmission within the in-vehicle Ethernet system, various network failures such as data skipping, packet loss, and node and network link disconnections may occur. These failures can lead to the loss of fundamental operating functions of control systems such as the braking system, steering system, and advanced driver assistance system. Consequently, the risk index of automotive information security is significantly heightened [5]. As one of the most  
Figure 1: Vehicle Ethernet bus network. widely utilized modes of transportation, it is imperative for automobiles to prioritize the information security of their in-vehicle networks. Neglecting this aspect could severely compromise the safety of vehicle operations and potentially endanger public safety as well. As evidenced by a landmark event in 2015, security researchers [PERSON] and [PERSON] lacked into a Jeep's multimedia system via WiFi and successfully infiltrated its core CAN bus network. This notable case underscores the critical need to safeguard both the multimedia and internal bus networks within automotive systems, as malicious actors could potentially manipulate crucial vehicle components. In light of this, the importance of ensuring robust security measures for in-vehicle networks cannot be overstated [6]. As the primary network infrastructure of autonomous vehicles, ensuring the security of in-vehicle Ethernet is crucial. Two main approaches are employed to address the security challenges of in-vehicle networks: cryptography-based message encryption and authentication mechanisms, and packet monitoring and analysis to detect malicious messages and network anomalies [7; 8; 9]. However, the high real-time demands of in-vehicle bus networks make traditional computer network security technologies computationally intensive and difficult to implement within electronic control units [10]. Therefore, it is essential to study the unique characteristics of in-vehicle bus networks alongside traditional cryptography to enhance security through improved encryption and authentication algorithms. In-vehicle Ethernet is pivotal for automotive active safety, thus requiring assurance of real-time performance, reliability, and security. To ensure the real-time performance of in-vehicle Ethernet, we conducted research on enhancing encryption and authentication algorithms to bolster defense capabilities. The upgraded encryption algorithm improves the encryption rate by 15% compared to the traditional method, while the enhanced authentication algorithm reduces computation time by half. By integrating these two improved algorithms, we propose a highly efficient security mechanism for in-vehicle Ethernet. To validate the efficacy of our proposed security mechanism, we conducted attack experiments on the CANoe platform, simulating braking, throttle, lights, and video playback functions, and assessed its defensive capabilities. The experimental results demonstrate that our designed security mechanism effectively safeguards the bus network's security and reliability without disrupting the normal communication function of in-vehicle Ethernet. The contributions of this paper are as follows:  
* AES-ECC Hybrid Algorithm: We develop a novel AES-ECC hybrid algorithm for critical vehicle control signals in Ethernet networks, balancing AES efficiency with ECC security. * Improved AES-128 (IAES-128): We propose IAES-128, optimizing AES-128 for multimedia entertainment data with a 15% faster encryption time. * Improved MD5 Authentication (IMD): We improve MD5 authentication (IMD) by 50% in computation time, ensuring efficient data integrity verification. * Comprehensive Security Mechanism: These algorithms are integrated into a robust security framework, rigorously tested via CANoe attack simulations to protect both critical and non-critical vehicle systems. * Validation Through Simulations: Validated through realistic cyberattack simulations, ensuring reliability in safeguarding autonomous vehicles from potential threats.