Go CCIE Go!! - A Cisco Certified Internetwork Expert

Ok, no-one answered this one so Ill pick it up
You are right, EIGRP makes life much simpler with the EIGRP external AD 170. Here is how it works…
Assume the two routers doing redistribution are R1 and R2 both running OSPF and EIGRP.
OSPF native routes (routes learned via OSPF) get redistributed into EIGRP by R1. As EIGRP external routes, they have an AD of 170. R2 recieves the route and has a decision to make - use the OSPF route or EIGRP route. OSPF AD is 110 so it uses that route (versus AD 170). Same thing works with R2 doing the redistribution. On the other hand, R1 ones redistributes the EIGRP native routes into OSPF. R2 recievies these routes via OSPF and has a decision to make - use the EIGRP route or OSPF? Internal EIGRP AD is 90 and OSPF is 110 - so EIGRP native routes are installed as EIGRP. Sumamry, in this scenario you will always have optimum routing - thanks to EIGRP external AD. Now, RIP into OSPF and vice-versa, is a little trickier…….!
Does that makes sense?
Dazzler
—–Original Message—– From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Monica Belluci Sent: 10 January 2008 05:56 To: Cisco certification Subject: Mutual Redistribution
Hi Guys,
If I do mutual redistribution on two ASBR connecting with same Autinomuos systems First (EIGRP) and Second (OSPF) . As I can understand EIGRP will automatically make it 170 AD for external routes so optimal path will be selected . please give comments..
thanks Nalini Roy