The best way to implemet secutiry in IIS is to add the user to the Usermanager for domains, then you need to remove the anonymous access in IIS for that directory/website, make sure that the internet guest account does not have any NTFS permissions on that directory. Then you can give the user the permissions that you want using NTFS permissions. As for using SQL, you could log the site to the ODBC plugin and then you could keep track of the activity of the users through that.