The TREE-topology is used for very large networks. I want to describe this topology with an example of a school network.
The root of the tree is a distributor (e.g. HUB, ...), which connects the various departments in the school. This first connection is called primary connection. Within a department you divide the network, e.g. in floors. This is called secondary connection.
Here I have two possibilities:
a) Collapsed Backbone: that means that each floor is connected with the building distributor
b) Distributed Backbone: that means that each floor has is own distributor which are connected. Just one distributor is connected to the building distributor
Each floor can be divided in various computer rooms. That¡¦s the tertiary connection.
"³ you can mix different topologies in one TREE-topology