1-9The basic message exchange procedure is as follows:1) A user sends a login request to the switch acting as a TACACS client, which then sends anauthentication start request to the TACACS server.2) The TACACS server returns an authentication response, asking for the username. Upon receivingthe response, the TACACS client requests the user for the username.3) After receiving the username from the user, the TACACS client sends an authenticationcontinuance message carrying the username.4) The TACACS server returns an authentication response, asking for the password. Upon receivingthe response, the TACACS client requests the user for the login password.5) After receiving the password, the TACACS client sends an authentication continuance messagecarrying the password to the TACACS server.6) The TACACS server returns an authentication response, indicating that the user has passed theauthentication.7) The TACACS client sends a user authorization request to the TACACS server.8) The TACACS server returns an authorization response, indicating that the user has passed theauthorization.9) After receiving the response indicating an authorization success, the TACACS client pushes theconfiguration interface of the switch to the user.10) The TACACS client sends an accounting start request to the TACACS server.11) The TACACS server returns an accounting response, indicating that it has received the accountingstart request.12) The user logs out; the TACACS client sends an accounting stop request to the TACACS server.13) The TACACS server returns an accounting response, indicating that it has received the accountingstop request.
