This object reports and controls the lifecycle and behavior of a MAC address filter entry: other(1) for an entry in use under different conditions, invalid(2) to remove the entry when written, valid(3) to add the entry when written, and dst-src-addr(4) to indicate the switch is actively filtering frames whose source or destination address matches this entry. Administrators write valid(3) to add a new filtering rule for a MAC address, or invalid(2) to remove one. For example, an admin blocking a known malicious device's MAC address would write valid(3) to add a filter entry for it, and the state would later show dst-src-addr(4) once the switch begins actively filtering frames to or from that address.