This is a 2 part SharePoint Server 2010 question.
1.- Is it possible to browse/navigate using the UI to _layouts/permsetup.aspx?
In MOSS this was done by click Groups > Settings > Setup Groups
2.- Is it possible to give a user access to: http://server/siteCol/DepSite
BUT not access to http://server/siteCol/
Or do they always have to have access to the SiteCollection before they can access a site within that site collection?
We have numerous site collections with subsites. We have subsite Owners granting access to users from other site collections, but they're always been greeted with Access Denied, until they have some sort of access (view) to the site collection.
Since the subsite owners aren't able to give access to the site collection, it's kind of useless allowing them to give users access to their own site. And we also don't want these "Other site collection users" access to the site collection.
Bob is the owner of the site Pedals.
Pedals is a site in the site collection Bicycles.
Bob only has Viewing rights in Bicycles.
Bob has a friend "Jay" in another site collection "Skates Boards".
Bob would like to give Jay view only access to Pedals.
So Bob goes to http://site/_layouts/user.aspx
and adds Jay to the Visitors Group.
Jay receives an email from firstname.lastname@example.org saying Welcome to Pedal Visitos.
Jay clicks the link and receives ACCESS DENIED
Bob calls Sam (the SP administrator) saying Jay can't access Pedals.
Sam adds Jay to Bicycle Visitors.
Now Jay has access to Bicycles and Pedals.