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Comment by tptacek | Hacker News Reader

See, this doesn't work either. One of the core jobs you have designing a secure transport is avoiding downgrade attacks, and the construction you just outlined is not only downgradable, it's explicitly downgradable, as a feature. That's not going to happen.

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So the answer is just to use only the weaker option forever?

No? There's a very specific technical problem that makes DNSSEC hard to deploy effectively. You can't just define it away. You have to pursue solutions that solve that problem. There's a whole huge solution space to draw from, but people are so path-dependent and so predisposed to like the IETF that DNSSEC is just the only discussion we seem to be able to have.

Fortunately, the WebPKI has been ratcheting (slowly) up security over the last 15 years, so when nothing else happens, which is what I predict, at least we'll be in a better place a decade from now.

Anything that doesn't eliminate the current model of "a whole pile of CAs of unknown and widely-varying reliability are ultimately-trusted by every TLS client in the world despite the numerous times that has caused serious problems for approximately everyone on the Internet" is IMHO not significantly better than what we have now. The trust is the problem, and shorter certificate lifetimes or restrictions on usage flags or the various other things trying to work around that issue don't solve it no matter how many of them are implemented -- they're bandaids on a shotgun wound.

But let's whiteboard for a bit: if you agree (as I assume you do) that the current situation is at least more insecure than it should be, and should ideally change fundamentally, and if you don't think DANE is the right fundamental change, what would you implement instead if you had the magic wand to make everyone agree to do it?

I would verify domain ownership using something other than DNS, and devise something more reliable than CAA records to lock down issuance authority. But I can't say enough how much I think DANE would be a direct step backwards for trustworthiness on the web. We would be immediately worse off in multiple ways. Any argument in favor of DANE has to work around the unreliability, the weak cryptography, and, most importantly, the lack of transparency.

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