About authentication exceptions
An authentication exception is used for those sites that users must be able to access without authenticating first, for example, for automatic Microsoft Windows updates.
Connect for Chromebooks
Your Smoothwall Filter contains a category named Connect for Chromebooks. This category contains all Google websites necessary for Google user authentication, such as, single sign-on. These websites must be accessible for all Chromebook devices and those serving the SSL / non-SSL login pages with the Google Sign-In button.