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Re: [OSPF] OSPF Information Hiding

Russ White <russ@cisco.com> Wed, 23 February 2011 15:28 UTC

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Date: Wed, 23 Feb 2011 10:29:12 -0500
From: Russ White <russ@cisco.com>
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Subject: Re: [OSPF] OSPF Information Hiding
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> OSPFv2, as specified in RFC 2328, states that a multi-access network's subnet is specified by the DR's Network-LSA LSID/mask and installed during the SPF graph traversal. Hence, without some form of signaling, there is no way to prevent other routers in the OSPF area from installing the subnet route (whether or not it is really needed for any purpose in the OSPF network deployment). 

So, in reality, this isn't about the way SPF is run, but the assumption
in RFC2328 that the LSID/subnet mask from the type 2 is the "correct"
subnet to put in the table when building the tree... Hmm...

Then it seems like the magic number is unavoidable in this case.

:-)

Russ

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