How to Get IP Addresses of Computers In Active Directory Domain

AS there is little crossover requirements I would recommend setting them up as suggested, one domain with appropriate OU's beneath them.

If setup with the relevant "sites" with at least one domain controller at each and with at least one Global Catalog at each site (no reason not to have each DC be a GC)

Once you migrate to the 100MB/s WAN even high volume DFS transfers would pose little issue.

Maintaining it as one domain with multiple sites and appropriate OUs for permissions, installations, group security etc. means that should all domain controllers in one site fail, all machines, with the exception of machines that are told specifically to look at one domain controller for authentication e.g. an application that is querying a domain controller for LDAP services, should still be able to log in and use network resources.

Over a 2Mb/s link this would be suboptimal but should be an edge case scenario, i.e. server room burns down but comms room is okay etc. Over a 100Mb/s link how is that any different to a normal domain config?

It can't be done the way you want. It just doesn't work that way. The ACLs (Access control lists) are stored on each file and folder. AD doesn't have a clue what folders and files (and servers) the group has been assigned to.

What you can do however, is use the AccessEnum tool from Microsofts Sysinternals. You can run this on a file server, and it will tell you who/what has access to each folder. You can then export this to a CSV for analysis in Excel.

_{(source: microsoft.com)}