HP 12500 Series Configuration Manual page 22

Figure 6 Basic message exchange process for a Telnet user
Host
1) The user logs in
4) Request for username
5) The user inputs the username
8) Request for password
9) The user inputs the password
14) The user logs in successfully
17) The user logs off
HWTACACS operates in the following manner:
A Telnet user sends an access request to the HWTACACS client.
1.
Upon receiving the request, the HWTACACS client sends a start-authentication packet to the
2.
HWTACACS server.
The HWTACACS server sends back an authentication response to request the username.
3.
Upon receiving the response, the HWTACACS client asks the user for the username.
4.
The user enters the username.
5.
After receiving the username from the user, the HWTACACS client sends the server a
6.
continue-authentication packet that carries the username.
The HWTACACS server sends back an authentication response, requesting the login password.
7.
Upon receipt of the response, the HWTACACS client asks the user for the login password.
8.
HWTACACS client
2) Start-authentication packet
3) Authentication response requesting the username
6) Authentication continuance packet with the
7) Authentication response requesting the login
10) Authentication continuance packet with the
11) Authentication response indicating successful
12) User authorization request packet
13) Authorization response indicating successful
15) Start-accounting request
16) Accounting response indicating the start of
18) Stop-accounting request
19) Stop-accounting response
12
HWTACACS server
username
password
login password
authentication
authorization
accounting