Re: Type-4 LSA and NSSA

Thanks Scott and Narbik for confirming my thoughts.

I think I finally found an "official" confirmation for that.

RFC 1587 The OSPF NSSA Option states on page 5:
"Type-7 LSAs are only flooded within the NSSA. The flooding of type-7 LSAs
follow the same rules as the flooding of type 1-4 LSAs."
But it describes at no point, that Type-4 LSAs will not be flooded into
NSSAs.

However, RFC 3101 The OSPF Not-So-Stubby Area (NSSA) Option, which obsoletes
RFC 1587, clearly states on page 5:
"Since Type-5 AS-external-LSAs are not flooded into NSSAs, NSSA border
routers should not originate Type-4 summary-LSAs into their NSSAs."

Cheers
Mike

2009/5/9 Scott Morris <smorris_at_internetworkexpert.com>

> Type 4's are used for next hop reachability to get to the Type 5 LSAs
> (ASBR). If you have no Type 5's, you have zero need for a Type 4 LSA. :)
>
> So I'd suggest that someone messed up in the book?
>
> *Scott Morris*, CCIE*x4* (R&S/ISP-Dial/Security/Service Provider) #4713

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Received on Sat May 09 2009 - 09:28:25 ART