What are the general steps a firewall uses to authenticate users?

What will be an ideal response?

1. The client makes a request to access a resource.
2. The firewall intercepts the request and prompts the user for name and password.
3. The user submits the requested information to the firewall.
4. The user is authenticated.
5. The request is checked against the firewall's rule base.
6. If the request matches an existing allow rule, the user is granted access.
7. The user accesses the desired resources.