D-Link DES-6500 Manual page 152

Shortest Path Tree
To build Router A's shortest path tree for the network diagramed below, Router A is put at the root of the tree and the
smallest cost link to each destination network is calculated.
The diagram above shows the network from the viewpoint of Router A. Router A can reach 192.213.11.0 through Router B
with a cost of 10 + 5 = 15. Router A can reach 222.211.10.0 through Router C with a cost of 10 + 10 = 20. Router A can
also reach 222.211.10.0 through Router B and Router D with a cost of 10 + 5 + 10 = 25, but the cost is higher than the
route through Router C. This higher-cost route will not be included in the Router A's shortest path tree. The resulting tree
will look like this:
DES-6500 Chassis-based Layer 3 Ethernet Switch Manual
Figure 6- 114. Constructing a Shortest Path Tree
128.213.0.0
5
192.213.11.0
Figure 6- 115. Constructing a Shortest Path Tree
Router A
0
10
Router B
5
Router D
10
222.211.10.0
151
10
Router C
10