# Efficient Secure Mechanisms for In-Vehicle Ethernet in Autonomous Vehicles
## 2 Background and Related Work
### Cybersecurity Hazards of In-Vehicle Ethernet
#### 2.2.2 Cryptographic Solutions  
To protect vehicle networks from cyberattacks, cryptographic solutions are essential. These solutions involve encryption and authentication technologies to secure communication and prevent unauthorized access:  
* [PERSON] et al. 's Broadcast Authentication Protocol: [PERSON] et al. proposed a backward-compatible broadcast authentication protocol for the CAN bus. This protocol is designed to be fully applicable without modifications to existing nodes [21]. * [PERSON] et al. 's LASAN Protocol: [PERSON] et al. introduced the Lightweight Authentication Protocol LASAN, which is suitable for in-vehicle networks. LASAN provides notable security and real-time advantages without requiring additional hardware support [22]. * [PERSON] et al. 's Keychain Authentication Mechanism: [PERSON] et al. proposed a unidirectional keychain delayed-exposure-based authentication mechanism for TTEthernet. This mechanism enhances message authenticity and reduces authentication delay while addressing system scheduling challenges through mixed-integer linear programming [23]. * [PERSON] et al. 's Security Framework: [PERSON] et al. developed a novel mechanism for securing applications in vehicles. This framework is integrated with Ethernet communication and the Service-Oriented Middleware-over-IP (SOME/IP) to bolster communication security [24]. * [PERSON] et al. 's Hardware Security Module (SECU): [PERSON] et al. proposed the SECU Hardware Security Module for key distribution and secure authentication. It also protects the ECU against attack messages before they are received [25]. * [PERSON] et al. 's Signal-Packing Method: [PERSON] et al. proposed a signal-packing method using the Next Decrease of Fit (NFD) algorithm, which facilitates swift message scheduling and minimizes Frame ID (FID) usage to control message load size and enhance transmission efficiency for FlexRay static segmented messages [26]. * [PERSON] et al. introduced PSRQ, a cryptographic scheme that combines Geohash with Coalesce Bloom Filter (CSC-BF) and Symmetric-key Hidden Vector Encryption (SHVE), to enhance privacy and query efficiency. PSRQ+ further improves security and range support, achieving \(100\times\) better efficiency compared to prior methods [27]. Challenges and Limitations of Existing Approaches:The original version of the Ethernet standard is widely acknowledged to offer relatively low levels of security. This has been a significant concern as the automotive industry increasingly adopts Ethernet for in-vehicle networks. The limitations of existing approaches include the following:  
1. Insufficient encryption mechanisms that do not provide adequate protection against sophisticated cyberattacks. 2. A lack of robust authentication protocols that can verify the integrity and authenticity of messages in real-time [28]. 3. Inadequate consideration for the unique challenges posed by the automotive environment, such as the need for low latency and high reliability in safety-critical systems [29]. Safety Mechanisms in Automotive Operating Systems: Widely used Automotive Operating Systems like AUTOSAR provide safety mechanisms like End-to-End (E2E) that include several safety mechanisms targeted at different Communication Failure modes [30; 31]. These mechanisms are designed to ensure data integrity and reliability in the face of various communication failures. It is crucial for researchers to investigate the Communication Failure modes and the safety mechanisms AUTOSAR provides to enhance the security of in-vehicle Ethernet networks. As the Ethernet protocol emerges as a relatively novel autonomous solution, there remains a lack of comprehensive studies on security protocols specifically tailored for self-driving cars. However, it is widely acknowledged that the original version of the Ethernet standard offers relatively low levels of security, a concern that has been underscored in numerous research endeavors [32].