Data transfer with the CAN data bus functions in much the same way as a telephone conference.
A subscriber (control unit) ”speaks“ data into the line network while the other subscribers ”listen in“ to this data.
Some subscribers will be interested in this data and will utilize it. The other subscribers will choose to ignore this data.
Components make up a CAN data bus
The CAN data bus comprises a controller, a transceiver, two data bus terminals and two data bus lines.
Apart from the data bus lines, the components are located in the control units. The functions of the control units are the same as before.

http://www.micro-tronik.com/learning/technical-information/a...


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Note added at 4 hrs (2017-06-09 11:16:46 GMT)
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Bus topology
This network topology is also referred to as a linear bus. The core element of a bus topology is a single cable to which all nodes are connected via short connecting cables (Fig.2). This topology makes it extremely easy to add other subscribers to the network. Information is transmitted by the individual bus subscribers in the form of so-called messages and distributed over the entire bus.

https://link.springer.com/chapter/10.1007/978-3-658-01784-2_...