Use http:// normally and only https:// ssl when authenticated

How do I correctly set up my Domino Web server so that when user browse the website it uses http:// port 80 protocol. But when user go into secure pages with logins authentication it will uses https:// ssl protocol port.At the moment my settings are:

Domino web engine: redirect to ssl port

Http session: load from internet site document.

At the moment when browser browse my website it’s being redirected to https:// ssl and http:// port 80 is not working. Thanks.

I just need https:// ssl port for authenticated section of the website and http:// port 80 for the rest of the website.