A CAN gateway is the controlled crossing point between in-vehicle network domains. Its design affects safety boundaries, diagnostics, cybersecurity, telemetry and the ability to evolve toward software-defined vehicle platforms.
A gateway should not blindly forward every frame. It needs allow lists, direction rules, bus-load limits and abnormal traffic detection. This protects domains such as powertrain and chassis from noisy body or infotainment networks while still allowing required signals to cross.
UDS and DoIP access should be mediated by policy. The gateway can authorize diagnostic sessions, restrict services, log requests and prevent broad access to ECUs that should not be visible from every diagnostic channel.
As vehicles adopt Ethernet backbones, gateways translate between signal-oriented CAN traffic and service-oriented data exchange. This is where legacy networks meet telemetry pipelines, OTA agents and SDV middleware.