ip verify source port-security

`ip verify source port-security` is a Cisco IOS command used to enable port security on a switch port. It restricts the number of MAC addresses that can access the port and can also verify the source MAC address of incoming packets. This command is typically used to prevent unauthorized devices from connecting to the network and to mitigate MAC address spoofing attacks. When enabled, the switch will automatically shutdown the port if an unauthorized device or MAC address is detected.