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Controller Area Network (CAN) allows multiple microcontrollers to all communicate on the same bus without any need for a "master/slave", "coordinator", "router" or anything similar. The advantage over other serial protocols is that it is robust for the automobile industry since CAN uses differential signals that can travel reliably at long distances. CAN also implements a lot high-level features in its "physical layer" (or in hardware), which makes it easy and cheap to develop a device that can be dropped onto the CAN bus of an automobile.