I wish to serve vector and raster data and metadata on the Internet, and I am planning to use the Geoportal. One condition for that is if the Geoportal is able to grant download privileges with regard to the user's profile. For instance, the administrator and advanced users are able to download data, but the simple user cannot. Is it technically possible?
Yes, it is technically possible. There are several ways to implement it. It is not an "out of the box" configuration. We've typically assisted clients with a solution like this through a services project or developer consulting.