1-1011) The HWTACACS server sends back an authentication response indicating that the user haspassed authentication.12) The HWTACACS client sends the user authorization request packet to the HWTACACS server.13) The HWTACACS server sends back the authorization response, indicating that the user isauthorized now.14) Knowing that the user is now authorized, the HWTACACS client pushes the configuration interfaceof the NAS to the user.15) The HWTACACS client sends a start-accounting request to the HWTACACS server.16) The HWTACACS server sends back an accounting response, indicating that it has received thestart-accounting request.17) The user logs off.18) The HWTACACS client sends a stop-accounting request to the HWTACACS server.19) The HWTACACS server sends back a stop-accounting response, indicating that thestop-accounting request has been received.Protocols and StandardsThe protocols and standards related to AAA, RADIUS, HWTACACS include:z RFC 2865: Remote Authentication Dial In User Service (RADIUS)z RFC 2866: RADIUS Accountingz RFC 2867: RADIUS Accounting Modifications for Tunnel Protocol Supportz RFC 2868: RADIUS Attributes for Tunnel Protocol Supportz RFC 2869: RADIUS Extensionsz RFC 1492: An Access Control Protocol, Sometimes Called TACACSAAA Configuration Task ListThe basic procedure to configure AAA is as follows:1) Configure the required AAA schemes.z Local authentication: Configure local users and related attributes, including usernames andpasswords of the users to be authenticated.z Remote authentication: Configure the required RADIUS and/or HWTACACS schemes, andconfigure user attributes on the servers accordingly.2) Configure the AAA methods: Reference the configured AAA schemes in the users’ ISP domains.z Authentication method: No authentication (none), local authentication (local), or remoteauthentication (scheme)z Authorization method: No authorization (none) , local authorization (local), or remote authorization(scheme)z Accounting method: No accounting (none), local accounting (local), or remote accounting(scheme)
