Re: [TLS] Consensus Call on draft-ietf-tls-dnssec-chain-extension

Peter Gutmann <> Thu, 19 April 2018 03:25 UTC

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From: Peter Gutmann <>
To: Nico Williams <>, Richard Barnes <>
Thread-Topic: [TLS] Consensus Call on draft-ietf-tls-dnssec-chain-extension
Date: Thu, 19 Apr 2018 03:25:24 +0000
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Subject: Re: [TLS] Consensus Call on draft-ietf-tls-dnssec-chain-extension
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Nico Williams <> writes:

>That's just silly.  Really, 7.5 years (relative, not absolute) measured in
>hours is plenty good enough, and more than outlives current device
>obsolescence.  This isn't subject to Moore's law or anything like it.

I don't know what devices you work with, but for the ones where my code is
used ten years is the baseline life expectancy, going out to 15-20 years for
longer-life ones (I still have to deal with SSH bugs from the late 1990s,
because the lifetime of the equipment that's used in is 20 years and counting.
I think I've finally managed to get away from having to do SSLv3 within the
last year or two).

OTOH I doubt any of these devices will do pinning, they just bake in the certs
at manufacture/provisioning, so I'm fine with any kind of lifetime.  Just
wanted to point out, yet again, that the entire world doesn't live in a "we
can patch the entire deployed base in 24 hours" situation.