| Configure the NAS for TACACS+. The command aaa new-mode installs the AAA commands for the router configuration. The CiscoSecure ACS server is defined by the command tacacs-server host IP address, with "IP address" being the address of the ACS server. Next, the shared secret key between the NAS and ACS server is loaded with the command tacacs-server key PassW0RD. PassW0RD is the shared secret key. The NAS now has AAA globally enabled.