Communication Interface Cards are specialized hardware expansion boards and bus modules engineered to provide controllers, industrial PCs, and drives with deterministic industrial Ethernet protocols such as EtherCAT and PROFINET. Installed directly into controller backplanes or PCI/PCIe slots, these cards offload network protocol stack execution from the host processor to achieve sub-millisecond motion synchronization and real-time network Determinism. Key hardware features typically include dedicated onboard communication coprocessors, dual RJ45 or M12 industrial Ethernet ports, link and activity status LEDs, hardware-level IEEE 1588 time synchronization support, and galvanic port isolation.