Re: [dnsext] DNSSEC, robustness, and several DS records

Francis Dupont <> Thu, 12 May 2011 22:18 UTC

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From: Francis Dupont <>
To: Doug Barton <>
In-reply-to: Your message of Wed, 11 May 2011 17:47:59 PDT. <>
Date: Fri, 13 May 2011 00:18:30 +0200
Cc:, Paul Hoffman <>
Subject: Re: [dnsext] DNSSEC, robustness, and several DS records
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 In your previous mail you wrote:

   A) Insert obligatory rant about why "should" and "may" should never be 
   used in standards documents.

=> I don't follow your idea...

   B) I don't think it takes even the smallest leap of imagination to say 
   that if the SHA-256 DS is invalid, and the SHA-1 DS is valid, the SHA-1 
   should be used and the SHA-256 should be ignored.
=> it is not a problem of imagination: either you implement what the
spec says or you implement something else. And IMHO the first option
is never a "bug".

   I think we could have a fine "angels-on-the-head-of-a-pin" debate about 
   what "present" means in the RFC text

=> present == is an element of the set

   but I have a hard time believing that the intent of the text is
   that if you have something that works it should be ignored in favor
   of something that doesn't.
=> but it is the intent: this is why I wrote there is no "valid"
in the spec (where my "valid" means your "works").

So I don't expect to see bind or unbound to change their behavior
unless/until a new rfc is published with another spec.