about_login
The optional login page is disabled by default to make initial setup and use as easy a possible.
You can enable this page to add a password requirement by selecting the Enable passphrase check box on the Options page under Manage Passphrase.
The login page presents a text box for entering a password before other SIP pages are accessible. 
Note: The password provides only minimal security. It is indented to prevent unauthorized changes to SIP settings.
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