Motivation for 10BASE-T1S

The ethernet in a switch-based architecture has numerous benefits, but there are disadvantages to this approach that 10BASE-T1S looks to overcome. The switch itself is an intelligent and expensive device adding both costs and complexity. Additionally, most Ethernet types require each connection to a node to be a fully dedicated point-to-point network from a physical network standpoint. 10BASE-T1S eliminates the need for a switch and the point-to-point requirement. It supports a BUS or multi-drop topology similar to many popular legacy automotive networks. The slower speed of 10 Mbit/s with its design features enables cabling, connectors, and the PHYs to be simplified, targeting lower cost.

Currently, numerous legacy networking technologies are used in different parts of a vehicle that do not require high bandwidth. For example, most powertrain networks comfortably use either CAN/CAN-FD or FlexRay. This and many other applications of networks in vehicles require less than 10 Mbit bandwidth; therefore, 100BASE-T1 or higher speed grades of Ethernet would be overkill for these use cases. The Automotive Ethernet community envisions that if Ethernet could be cost-effective and robust even for sub 10 Mbit/s networks in a vehicle, then the overall architecture could be simplified by using a single base technology for all vehicle networks. The need for a complex gateway ECU to transfer data between different network types could be reduced or eliminated. By supporting a multi-drop architecture, the number of PHYs needed can also be reduced. Another benefit is Ethernet message routing, MAC/IP, would be the same throughout the vehicle, e.g. IP everywhere.

With the introduction of 10BASE-T1S, it is possible to reduce or eliminate gateways and PHYs count.

Intrepid’s 10BASE-T1S Hardware