As vehicles get equipped with increasingly complex sensors and processors, the communication requirements become more demanding. Traditionally, vehicles have used specialized networking technologies designed to guarantee bounded latencies, such as the controller area network (CAN) bus. Recently, some have used dedicated technologies to transport signals from cameras, lidars, radars, and ultrasonic sensors. In parallel, IEEE working groups are defining Ethernet standards for time-sensitive networks (TSN). This paper describes an Ethernet-based architecture with provable guaranteed performance and simple configuration that is suitable for supporting the communication requirements of in-vehicle networks.