RIP Justification

Jack Carrozzo jack at
Thu Sep 30 21:11:40 UTC 2010

As it was explained to me, the main difference is that you can have $lots of
prefixes in IS-IS without it falling over, whereas Dijkstra is far more
resource-intensive and as such OSPF doesn't get too happy after $a_lot_less
prefixes. Those numbers can be debated as you like, but I think if you were
to redist bgp ospf on a lab machine you'd get the point.

Disclaimer: I've never run IS-IS operationally, just in the lab.


> Which makes no sense to me. I originally looked at both and thought OSPF to
> be inferior to IS-IS. That being said, OSPF is supported on more (and
> cheaper) hardware. IS-IS can have additional licensing with some hardware
> (where OSPF does not) and is often considered a "service provider" protocol
> by vendors.
> Jack

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