Re: [sidr] draft-ietf-sidr-bgpsec-protocol-13's security guarantees

Rob Austein <sra@hactrn.net> Wed, 09 September 2015 01:07 UTC

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Date: Tue, 08 Sep 2015 21:07:09 -0400
From: Rob Austein <sra@hactrn.net>
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Subject: Re: [sidr] draft-ietf-sidr-bgpsec-protocol-13's security guarantees
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Hmm, I would have thought we'd want to keep the chaining, in the sense
that non-originating would sign the previous signature.  I've no real
objection to signing everything else again, it's just removal of the
previous signature that I find odd here.

The benefit I see to keeping the signature chaining is that it adds an
ordering constraint to the signatures (signature A must have been
created after signature B), corresponding to the order in which we
expect the update to travel between signers.  This seems like a good
thing, and I don't see why we'd want to remove it.  As you've
demonstrated, it doesn't remove all possible forms of mischief, but it
raises the bar a bit, and it's cheap, so why not?

Am I missing something?  Where's the benefit in removing the chaining?