Composability and compositionality in CAN-based automotive systems based on bus and star topologies

Controller Area Network (CAN) is the most widely used field bus protocol in the automotive domain. The development process of today´s cars follows the well established automotive V-Model. Traditional bus-based CAN makes the development an ever increasing challenge. For example, the introduction of a single additional CAN message influences the timing of already existing messages and thereby increases testing and integration efforts. The lack of composability and compositionality of traditional CAN leads to an overhead in the whole development cycle. In this paper we propose a development process that is based on a time-triggered CAN router. We examine the influence of our proposed development approach on major phases of the automotive V-Model. Our evaluation is based on CAN traffic of a mass-produced car by a major car manufacturer and a Fiel Programmable Gate Array (FPGA) based prototype implementation of the CAN router. From the results we gathered during our evaluation we conclude that a CAN router based development approach has the potential to simplify the development efforts that have to be undertaken by car manufactures.