Switch# configure terminal
Switch(config)# dot1x system-auth-control
Switch(config)# aaa new-model
Switch(config)# aaa authentication dot1x default radius
Switch(config)# radius-server host <i>192.168.123.23<i> auth-port 1812 key <i>secret<i>
Switch(config)# interface <i>fa1/10<i>
Switch(config-if)# switchport mode access
Switch(config-if)# dot1x pae authenticator
Switch(config-if)# dot1x port-control auto
Switch(config-if)# end
Switch# show dot1x interface <i>fa1/10<i> details