What are the key requirements for automotive ECU bootloaders?

Automotive bootloaders enable field software updates while ensuring reliability. Key requirements include: Fail-safe operation (recovery from interrupted updates), security (authenticated/encrypted updates, secure boot), protocol support (UDS programming services), memory management (flash driver, block handling), hardware abstraction, watchdog handling, minimal memory footprint, and compliance with OEM specifications. Advanced bootloaders support A/B partitioning for rollback capability. Safety-critical ECUs may require hardware security modules (HSM) and additional validation before activating new software.