Your company has a main office and a branch office.
You discover that when you disable IPv4 on a computer in the branch office, the computer authenticates by using a domain controller in the main office.
You need to ensure that IPv6-only computers authenticate to domain controllers in the same site.
What should you do?
A. Configure the NTDS Site Settings object.
B. Create Active Directory subnet objects.
C. Create Active Directory Domain Services connection objects.
D. Install an Intra-Site Automatic Tunnel Addressing Protocol (ISATAP) router.
Correct Answer: B
Explanation/Reference:
http://technet.microsoft.com/en-us/library/cc754697.aspx
Understanding Sites, Subnets, and Site Links
Sites overview
Sites in AD DS represent the physical structure, or topology, of your network. AD DS uses network topology information, which is stored in the directory as site, subnet, and site link objects, to build the most efficient replication topology. The replication topology itself consists of the set of connection objects that enable inbound replication from a source domain controller to the destination domain controller that stores the connection object. The Knowledge Consistency Checker (KCC) creates these connection objects automatically on each domain controller.
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Associating sites and subnets
A subnet object in AD DS groups neighboring computers in much the same way that postal codes group neighboring postal addresses. By associating a site with one or more subnets, you assign a set of IP addresses to the site.
Note
The term "subnet" in AD DS does not have the strict networking definition of the set of all addresses behind a single router. The only requirement for an AD DS subnet is that the address prefix conforms to the IP version 4 (IPv4) or IP version 6 (IPv6) format.
When you add the Active Directory Domain Services server role to create the first domain controller in a forest, a default site (Default-First-Site-Name) is created in AD DS. As long as this site is the only site in the directory, all domain controllers that you add to the forest are assigned to this site. However, if your forest will have multiple sites, you must create subnets that assign IP addresses to Default-First-Site-Name as well as to all additional sites.
