Modbus TCP · EtherNet/IP · PROFINET · Switch hops + WAN round-trip latency
When to use: Use this to estimate the round-trip communication latency between a controller and a field device across an industrial Ethernet network. Total latency is built from protocol stack processing, per-switch store-and-forward delay, frame serialization, cable propagation, and any WAN link. This determines the fastest practical poll/update rate and whether the link is fast enough for closed-loop control versus supervisory monitoring.