A Joint Safety and Security Analysis of message protection for CAN bus protocol

One of the prominent challenges of the automotive-transportation system is represented by the integration of security and safety properties within protocols, applications and connectivity mechanisms. A joint safety/security design can sometimes expose to trade-offs, since their requirements may not match perfectly or even be incompatible. This paper analyses an example of security and safety design, by combining integrity with encryption considering the constraints of a typical CAN protocol and real-time traffic. The analysis is presented modelling differently attackers, packet fragmentation issues and the residual probability of error of the combined scheme