How does SecOC (Secure Onboard Communication) protect vehicle networks?

SecOC (AUTOSAR standard) provides message authentication on CAN/CAN-FD networks using: MAC (Message Authentication Code) attached to messages computed with symmetric keys, freshness values (counters or timestamps) preventing replay attacks, and configurable authentication scope. Implementation requires: Key management infrastructure, synchronized freshness counters across ECUs, truncated MAC handling within CAN message limits, and latency impact consideration. SecOC protects against message spoofing but not against DoS attacks. Key distribution and secure storage in HSM are critical. SecOC is mandatory for safety-relevant communication in new vehicle architectures.