This read-write field toggles whether the SSH server will accept traditional username-and-password logins authenticated through the router's standard AAA at all. Admins care because disabling this, while keeping public-key authentication enabled, forces all SSH access to be key-based, eliminating password-guessing attacks entirely. For example, an admin disables this after rolling out public keys to all admin accounts, ensuring SSH access can no longer be attempted with just a stolen or guessed password.