The Controller Area Network (CAN) network protocol developed was by Robert Bosch GmbH initially for vehicle systems, but it is coming into use for linking distributed controllers, sensors etc in other fields.

CAN is a CSMA/CD protocol (some sources have CSMA/CR for similar protocols) that uses non-return to zero coding with bit stung. It supports speeds of up to 1Mb/s so is an SAE class C protocol, suitable for real time control applications. There is a brief explanation of the classes of protocols in section 3.1. Messages are not addressed to intended recipients, but the sender's identier is included, and this tells the receivers what data it contains so the receiver ignores it if it is not interested. Messages' identiers give the priority of the message, so the priority of messages is decided at the design stage.