CAN bus

To update the rest of the car, that gateway must relay the new software sequentially to dozens of individual electronic control units, or ECUs, scattered throughout the vehicle.

But the challenge for the attacker there is the wiring itself, because in those distributed models, the gateway is pushing updates over legacy networks like CAN or LIN buses.

Which are incredibly slow, highly constrained networks.

Right, lacking the bandwidth for heavy payloads.

And these DCUs have significantly more computing power.

Way more.

They mix higher speed Ethernet backbones for communication between the domains and then use faster legacy networks like CAN FD for the final mile to their subordinate sensors and actuators.

Let's clarify CAN FD mechanically.