ation, but be aware that creating a login method list doesn't automatically result in the creation of a ppp method list with the same name. If you want to have login and PPP method lists with the same names, you'll need to create them both: aaa authentication login GAD-Login group GAD-Servers aaa authentication ppp GAD-Login group GAD-Servers PPP authentication PPP authentication is used when Point-to-Point Protocol connections are initiated into the router. These can include modem connections into a serial interface, or con- nections of high-speed serial links such as T1s. The possible methods for PPP authentication using AAA are: if-needed If a user has already been authenticated on a TTY line, do not authenticate. Query a Kerberos 5 authentication server for authentication information (only for PAP). local Use locally configured usernames and passwords (entered in the configuration of the device itself). local-case Same as local, but the usernames are case-sensitive. This method essentially removes authentication. If none is the only method, there is no challenge. group radius Query the list of RADIUS servers for authentication information. group tacacs+ Query the list of TACACS+ servers for authentication information Custom (group group-name) Query a custom group as defined in the local configuration. AAA Authentication These methods are referenced in ppp method lists the same way that methods are referenced in login method lists. An interesting addition to the list of methods is if- needed. This method instructs the router to authenticate the incoming connection only if the user presented has not already been authenticated on a VTY, console, or aux line. Here is a sample ppp method list: aaa authentication ppp default group tacacs+ local-case Applying Method Lists Once you have created a method list, it needs to be applied to the interface or line where you would like it to take effect. With login authentication, the command login is used to apply an authentication method list. Here, I'm applying the GAD- Lo