User account authentication secures a Cisco console line by requiring a configured username and password instead of relying on one shared line password. Configure the console with `line con 0`, then select account authentication with `login local`. section 5.1 section 5.1.2
Key configuration and behavior:
- `login` and `login local` are mutually exclusive: `login` uses the line password, while `login local` uses configured user accounts. section 5.1.2
- User accounts provide more granular access control and activity tracking than a simple line password. section 5.1.2
- Console and VTY users normally enter user EXEC mode at privilege level 1; `enable` reaches privilege level 15. section 5.1.2
- A user account can specify a default privilege level, such as `username jeremy privilege 15 secret ccna`, bypassing the need for `enable`. section 5.1.2
Console login sequence
After configuring a user account and `login local` on the console line, the device prompts for `Username:` and `Password:` and then presents the `SW1>` user EXEC prompt.
