The use of networks for communications between the Electronic Control Units (ECU) of a vehicle in production cars dates from the beginning of the 90s. The speciﰅc requirements of the diﰄerent car domains have led to the development of a large number of automo- tive networks such as LIN, CAN, CAN FD, FlexRay, MOST, auto- motive Ethernet AVB, etc.. This report ﰅrst introduces the context of in-vehicle embedded systems and, in particular, the requirements imposed on the communication systems. Then, a review of the most widely used, as well as the emerging automotive networks is given. Next, the current eﰄorts of the automotive industry on middleware technologies which may be of great help in mastering the heterogeneity, are reviewed, with a special focus on the proposals of the AUTOSAR consortium. Finally, we highlight future trends in the development of automotive communication systems.