OSPF Hierarchical network

[sudhakara.py]

Hi 

I know OSPF operation, I have done configuration many time.

I would like to know what is hierarchical network design in OSPF, 1. why do need that ?  2.How to design that ? 3. If not have hierarchical design what happens?

Please answer.

[Joseph W. Doherty]

duplicate post - see https://supportforums.cisco.com/discussion/13037981/ospf-hierarchical-network