Evaluation of Vehicle System Performance of an SAE J1939-91C Network Security Implementation

CAN bus network proved to be efficient and dynamic for small compact cars as well as heavy-duty vehicles (HDV). However, HDVs are more susceptible to malicious attacks due to lack of security in their intra-vehicle communication protocols. SAE proposed a new standard named J1939-91C for CAN-FD networks which provides methods for establishing trust and securing mutual messages with optional encryption. J1939-91C ensures message authenticity, integrity, and confidentiality by implementing complex cryptographic operations including hash functions and random key generation. In this paper, the three main phases of J1939-91C, i.e., Network Formation, Rekeying, and Message Exchange, are simulated and tested on Electronic Control Units (ECUs) supporting CAN-FD network. Numerous test vectors were generated and validated to support SAE J1939-91C. The mentioned vectors were produced by simulating different encryption and hashing algorithms with variable message and key lengths. Moreover, the output vectors of each phase were passed to the subsequent phase to build up a complete scenario. The obtained simulation results will be used in the future for assessing the benefits of the standard as well as identifying potential strengths or possible shortcomings of the new protocol and to help suggest recommended enhancements and modifications.