OSPF single area limit

[grodoni]

on a network with 6 x cat6500, 10 x 3750, 20 x 2600routers and a total of about 200 routes, are there any inconviniences to use OSFP with a single area design (with a stabel fiber optic backbone) ?

If yes, which would be the limit for a single aread design ?

[Georg Pauwen]

Hello,

although normally, your design should not be a problem - the rule of thumb is that a single area should contain between 30 and 40 routers max - there are different design considerations. 200 routes does not sound like a lot, but if there are many topology changes, router CPUs might be a problem.

You might want to check this document, it explains the different design factors:

OSPF Design Tips

http://www.cisco.com/en/US/partner/tech/tk365/tk480/technologies_white_paper09186a0080094e9e.shtml#t39

Apart from that, your best bet is to build the network and monitor the performance. If performance degrades, you might have to split it into two or more areas.

HTH,

GP