This read-only enum reports which forwarding mode, storeandforward(1) or cutthru(2), this port is actually operating in right now, as distinct from the configured setting in ciscoTsPortCfgForwardingMode which might be set to auto. When the config object is auto(1), this is the only place to see what the Direct Cut algorithm actually decided at this moment, which matters when diagnosing latency or error-tolerance behavior that seems inconsistent with the configured mode. Seeing storeandforward(1) here on a port configured for auto tells the admin recent error conditions pushed the port into the safer mode.