You need to look at the Extranet plugin - http://www.composite.net/Add-on-Market/Packages/Composite.Community.Extranet ($500 though...)
The permissions in the Composite system only affect the users logged into the Composite Admin Interface - they have no effect on the frontend.
You could also develop your own implementation using FormsAuthentication for example.
The permissions in the Composite system only affect the users logged into the Composite Admin Interface - they have no effect on the frontend.
You could also develop your own implementation using FormsAuthentication for example.