This TruthValue enables or disables destination-MAC-address frame-matching criteria for all loopback streams on the port, except it does not apply to the efm-oam-remote and efm-oam-remote-timed loopback types. An administrator turns this on to restrict which frames get looped back based on their destination MAC address rather than looping every frame indiscriminately. For example, enabling this control alongside setting cmEthernetTrafficPortLoopbackDestMacAddress lets a technician loop back only traffic destined to a specific test MAC address during a service verification test.