Chapter 5: Managing Active Directory Sites and Troubleshooting Replication
When I first learned about Active Directory sites, the concept was explained to me as being locations of readily available connectivity.
There's an easy analogy for it: islands. In island states, people live on islands, but not everything they need might be available on their island. Additionally, something on their island might break, and there are only a few trade routes for goods and services.
In this analogy, the trade routes between geographical locations are the networking connections between Active Directory sites, the islands of readily available connectivity. The island's roads are that readily available connectivity: you can use them all you want, without additional cost.
Not many organizations place the domain controllers that hold Flexible Single Master Operation (FSMO) roles in poorly connected Active Directory sites. Many networking topologies for organizations feature a hub...