Topology 3: simple tiered Historian topology for a modem configuration

In a modem configuration, the network bandwidth between the tier-1 and the tier-2 historians is limited by 56 Kbps. Because the tag count and the replication data rate of the tier-1 historian should be very limited, it would be sufficient to consider only one tier-1 historian performing simple replication to one tier-2 historian over a modem network.