Controller Area Network - abbreviated CAN, a serial bus network of microcontrollers that connects devices, sensors and actuators in a system or sub-system for real-time control applications. There is no addressing scheme used in controller area networks, as in the sense of conventional addressing in networks (such as Ethernet). Rather, messages are broadcast to all the nodes in the network using an identifier unique to the network. Based on the identifier, the individual nodes decide whether or not to process the message and also determine the priority of the message in terms of competition for bus access. This method allows for uninterrupted transmission when a collision is detected, unlike Ethernets that will stop transmission upon collision detection.

Controller area networks were first developed for use in automobiles. Equipped with an array of sensors, the network is able to monitor the systems that the automobile depends on to run properly and safely. Beyond automobiles, controller area networks can be used as an embedded communication system for microcontrollers as well as an open communication system for intelligent devices.

The controller area network, first developed by Robert Bosch in 1986, is documented in ISO 11898 (for applications up to 1 Mbps) and ISO 11519 (for applications up to 125 Kbps).

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