Tools for intersite replication: site links and site link bridges
When you configure replication between sites, two additional objects are available to help control the replication topology: site links and site link bridges. An efficient, reliable replication schema depends on the configuration of site links and site link bridges.
An overview of Site Links
A site link is an object that represents a connection between sites that can carry traffic at a uniform cost.
As an administrator, you associate sites with site links, creating an optimized, cost-effective replication scheme.
When you configure a site link, you specify values for cost, interval, and schedule. The KCC uses these values to manage replication between sites.
The following slide show below demonstrates this:
Configuring Site link in Active Directory
The KCC uses values for cost, interval and schedule to manage replication between sites.
For example, if you create a site link called XYZ that connects site X, site Y, and site Z, replication traffic can occur between all pairs of sites
at the same cost
If you have a site X that has a slow connection to the site Y and a fast connection to site Z
You would create a site link XY with values that reflect a slow connection
and a site link XZ with values that reflect a fast connection.