The correct matches are as follows:
- Site: A subnet or subnets connected by a high-speed link
- Site link: A mapping in Active Directory of the connection between sites
- Subnet: A physical segment of the network that uses IP addresses derived from a single network ID
- Domain: The basic security boundary in a Windows network, which has its own security policies
- Forest: A group of domain trees that share a noncontinguous namespace
Site links allow you to define what sites are connected to each other and the relative cost of the connection.
When you create a site link, you specify which sites are connected by this link and what the cost or metric of the connection is in a relative-costing model. For instance, three sites A, B, and C could be connected to each other, but because you understand the underlying physical network, you might feel all traffic should be routed through the A site.
This would require you to configure to two site links: A to B and A to C.
If at a later time additional physical network connections were established between B and C, you could set up one more site link and connect B and C together. If you configure all three site links with an equal cost say, 100 traffic could then flow across the B-to-C link instead of from B to A to C.
This is because the total cost to use the B-to-C link would be 100 and the total cost to use the B-to-A-to-C route would be 200, which is more expensive.
Once you create a site object, you need to define one or more subnets for the site. The Active Directory uses this information for replication and traffic flow processes, so you are essentially telling the Active Directory which IP subnets belong to which site.
To define a subnet(s) for a site, follow these steps:
- In Active Directory Sites and Services, expand the Sites container and select the Subnets container.
- Click Action ->New Subnet. The New Object-Subnet window appears, as shown in Figure 3-3.
Enter the subnet and the mask for the subnet. The console automatically translates this information in a subnet name in the form of network/bits-masked. Select the site to which this subnet physically belongs, and then click the OK button.