We have a network of approximately 5000 end nodes. The backbone consists of the traditional Cisco model with 2 cores, a data centre layer and distribution layer based on location to feed different terminals across the Airport. All backbone devices are Cat 6500's utilising a mixture of sup 720 / sup 2 all with the MSFC duaghter cards.
I am due to start a new project to introduce a resilient switch within each distribution block and thought it worthwhile to address / optimise any routing.
We currently have all OSPF devices configured in Area 0. It isn't causing us any issues, and memory utilisation is fairly low, with approximately 450 routes at the core.
At what point should I consider segregating the distribution switch blocks into different areas and introduce ABR's ?
Bearing in mind that each distribution switch provides connectivity for somewhere between 1500 - 2000 end hosts.
Thanks in advance.