As vehicles consolidate functions onto central and zonal computers, the network connecting them must carry far more data than CAN ever could — without losing the timing guarantees safety functions depend on. Automotive Ethernet, paired with Time-Sensitive Networking (TSN), is the backbone that makes this possible.
CAN and CAN FD are excellent for control signals but top out in the low single-digit megabits per second. Cameras, radar, lidar and high-resolution displays push hundreds of megabits to gigabits. Automotive Ethernet (100BASE-T1, 1000BASE-T1 and multi-gig) supplies that bandwidth over lightweight single-pair cabling suited to vehicle harnesses.
Standard Ethernet is best-effort: it can drop or delay frames under load, which is unacceptable for brake or steering data. TSN is a set of IEEE standards adding time synchronization (802.1AS), traffic scheduling (802.1Qbv), frame preemption and bandwidth reservation. Together they let safety-critical streams share one network with bulk video while keeping bounded, predictable latency.
In a zonal design, zone controllers aggregate nearby sensors and actuators and connect to central compute over an Ethernet ring or star. The gateway role shifts from pure CAN routing to translating legacy buses into service-oriented Ethernet streams. This is what shrinks wiring, enables OTA-updatable functions and gives the software-defined vehicle a single high-speed nervous system.