Cars and trucks are quickly becoming Formula One race cars—at least in terms of data. With more types of onboard devices requiring near-instantaneous data transmission than ever before, engineers and designers are challenged to accommodate the accelerating need for bandwidth and speed.
At the core of just about every innovation today, from advanced driver-assistance systems (ADAS) to collision detection sensors and infotainment systems, is data. Traditional automotive data networking technologies such as controller area networks (CANs), local interconnect networks (LINs), and Media Oriented Systems Transport (MOST) were not designed to support the bandwidth these systems demand. In fact, the need to implement time-sensitive networking (TSN) standards has forced engineers to look outside the automotive arena for alternative transit solutions.
Ethernet is the obvious choice. This staple of the IT world, while not exactly new to automobiles, is being applied with increasing frequency, and for a number of reasons. Ethernet technology allows for fewer cables of lighter weight—not an insignificant advantage. Also, automotive engineers know that Ethernet is proven technology, supported by many device manufacturers, and has a strong hardware/software support ecosystem.
Yet Ethernet can’t satisfy all requirements for data networking performance—which is why there’s also a need for TSN technology. TSN guarantees that high-quality data packets are delivered with low latency, something Ethernet doesn’t natively support. In addition, TSN provides a network-wide clock for packet synchronization across systems, and prioritizes time-sensitive data streams over those of lower priority. Finally, it guarantees a minimum level of availability for emergency transmission.
Drive Testing Limitations
Validating high-speed Ethernet devices for automotive use is a complex undertaking.
Automakers, along with in-vehicle device and system OEMs, have stringent requirements for latency, synchronization, conformance, availability, and QoS. These requirements must be met, as consumers must be able to rely on their cars and trucks for safe, reliable performance. The potential cost of failure—not to mention recalls, liability, and damaged reputations—is simply too high.