cmEthernetTrafficPortShapingEnabled is a read-write boolean that manages Ethernet Port Shaping; when enabled, the values in cmEthernetTrafficPortShapedSpeedLo (and its high-order counterpart) become applicable. An administrator enables this to smooth this port's outgoing traffic to a rate below its physical line rate, which is useful for enforcing a contracted bandwidth cap independent of the port's raw negotiated speed. For example, selling a customer a 500Mbps service over a physical 1Gbps port would require enabling shaping here so traffic is capped at the contracted rate rather than bursting to the full port speed.