Many switches and routers have all of their interfaces enabled by default, right out of the box. As we've discussed, hardening—that is, closing unused ports—helps to secure a network by closing possible entry points. There are several approaches, standards, and methods used to secure internetworking devices, especially routers and switches, most of which are port-based network access control (PNAC) methods.
Port security
Port-based security
In general terms, port-based security secures the interfaces (ports) of a switch by limiting the number or specific devices that may forward packets or frames to one or more of its ports. Port security has two approaches:
- Dynamic locking: This sets the maximum number...
