Something Old, Something New…
Some time back a reader sent this question in—
Is there some list of design fundamentals which were “true” or at least “good rules of thumb” in the past (2 months to 20 years and beyond) which are still proclaimed as true and good, which we need to throw out, or at least question closely today?
It’s an interesting question—the problem is, of course, that there are two sorts of answers to this type of question. The first is rather specific, and the second is rather general. Let’s try the more specific answer first, and see if we can get to the more general one.
There are several rules of thumb that are no longer useful today.
OSPF and IS-IS flooding domains should be limited to 50/100/200 routers/intermediate systems. The old “50 in an area rule” is something several of us asked to be removed from Cisco Online something like 10 years ago, as it didn’t even apply then. I’ve heard 200 more recently, but the reality is—there is no right number here. I just did a two post series on dividing up flooding domains that might be useful here (part 1 and part 2).
There are provider Continue reading