What is a gateway ECU and what functions does it perform?

A gateway ECU connects different vehicle networks, translating messages between protocols and providing network isolation. Functions include: Protocol translation (CAN to CAN-FD to Ethernet), message routing and filtering, network segmentation for security and fault isolation, diagnostic access management, sleep/wake control coordination, firewall functionality preventing unauthorized access, and data logging. Modern centralized architectures may use a central gateway or domain controllers performing gateway functions. The gateway is critical for vehicle cybersecurity.