This read-write value selects the authentication method, none, local, radius, or tacacs, for a given entry in the user authentication provider table, with the rule that at least one provider must not be none and no method can be used twice; changing a provider to none shifts lower-priority providers up to fill the gap. An admin configures a prioritized chain of authentication providers, such as trying RADIUS first and falling back to local accounts. For example, setting the first provider entry to radius(3) and a second to local(2) makes the device try RADIUS authentication first, falling back to local accounts if RADIUS is unavailable.