The configuration given below is a suggested solution to the lab. Notice that RouterB uses the command area 10 stub to specify that Area 10 is a stub area. Also notice that RouterC uses the command area 20 stub no- summary
to specify that Area 20 is a totally stubby area. Recall that the dif-
ference between a stub area and a totally stubby area is that a totally stubby area does not receive summary Link State Advertisements. Another impor- tant design distinction is that the concept of a totally stubby area is specific to Cisco routers.