[Cryptography] Certificates and PKI

[Ben Laurie]

On 29 December 2014 at 18:45, Viktor Dukhovni <cryptography at dukhovni.org> wrote:
> On Mon, Dec 29, 2014 at 03:40:00PM +0000, Ben Laurie wrote:
>
>> >     m9ktr713mv89v98bat896geo4it3stbd.example. NSEC3 1 0 1 BEEF M9KTR713MV89V98BAT896GEO4IT3STBF
>> >
>> > From such a domain served by a DNSSEC hosting provider with many
>> > client zones one can elicit an essentially unlimited number of
>> > signed responses.
>>
>> OK. But why would we care for DT (i.e. DNSSEC transparency) - all we
>> care about, surely, is records that can influence the beholder's view
>> of the domain key(s)?
>
> Denial of existence of TLSA RRs is significant.  As is denial of
> existence of NS/DS records which might allow the parent to serve
> a child zone directly.

I agree with the latter but not the former - denial of a TLSA record
requires a signature (assuming you're using DNSSEC - if you're not, DT
is not for you). All we need to secure is that signature. So, NS/DS
matter but TLSA do not.