Yukito, the permissions can be set through the User module, for each group of users.
Well, it doesn't control access permissions to pages. What I need is to control in bulk which groups can access website pages. Such as, I have a homepage which is accessible to everyone, but also have other pages under it, that used to be locked to registered and approved users. That's the kind of permission I want to apply in bulk.
What the usergroups do is control who can interact like post things or use the guestbook and also, manage the website in general.
Because I know the site will get bigger one time, so I would like a way to control access to groups of pages.