Which two external authentication methods are supported by the Junos OS for user authentication?

You can configure devices running the Junos OS to be both a RADIUS and TACACS+ client, and you can prioritize the order in
which the software tries one or more of the three different authentication methods.
For each login attempt, the Junos OS tries the authentication methods in order, until the password is accepted. The next method
in the authentication order is consulted if the previous authentication method failed to reply or if the method rejected the login
attempt. If no reply (accept or reject) is received from any of the listed authentication methods, the Junos OS consults local
authentication as a last resort.