PLCA is a mechanism for 10BASE-T1S that avoids collisions and coordinates bus access.

PLCA stands for Physical Layer Collision Avoidance and is a mechanism for 10BASE-T1S multipoint networks. It improves throughput, fairness, and latency by coordinating transmission opportunities so that physical collisions on the shared bus are largely avoided. PLCA is particularly important because classic Ethernet with purely CSMA/CD on shared automotive multidrop lines would be much less predictable. For zonal or edge-related vehicle architectures, PLCA makes 10BASE-T1S significantly more plannable and closer to the deterministic properties of classic automotive buses.