This read-write PortList specifies the set of interfaces that a bulk port-lock configuration entry applies its parameters to. Admins use this to configure port-locking settings (mode, action, trap behavior) across many ports in a single operation rather than one at a time, which matters for efficiently rolling out a security policy across a large port count. For example, an admin securing an entire access-layer wiring closet could set this PortList to all edge ports at once instead of configuring each individually.