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Comment by grey-area | Hacker News Reader

Since you’ve thought about it a lot, in an ideal world, should CAs exist at all?

There's no such thing as an ideal world, just the one we have.

Let's Encrypt was founded with a goal of rapidly (within a few years) helping get the web to as close to 100% encrypted as we could. And we've succeeded.

I don't think we could have achieved that goal any way other than being a CA.

Sorry was not trying to be snarky, was interested in your answer as to what a better system would look like. The current one seems pretty broken but hard to fix.

No they should not

DANE is the way (https://en.wikipedia.org/wiki/DNS-based_Authentication_of_Na...)

But no browser have support for it, so .. :/

Much as I like the idea of DANE, it solves nothing by itself and you need to sign the zone from tampering. Right now, the dominant way to do that is DNSSEC, though DNSCurve is a possible alternative, even if it doesn't solve the exact same problem. For DANE to be useful, you'd first need to get that set up on the domain in question, and the effort to get that working is far, far from trivial, and even then, the process is so error prone and brittle that you can easily end up making a whole zone unusable.

Further, all you've done is replace one authority (the CA authority) with another one (the zone authority, and thus your domain registrar and the domain registry).

The zone authority already superseeds the CA authority in all ways

When I manage a DNS zone, I'm free to generate all certificates I want

I tried filing an issue against the chromium project for DANE support a year or two ago and they closed the issue with a nonsense reason.

This is a great question. If we don't have CAs, how do we know if it OK to trust a cert?

Are there any reasonable alternatives to CAs in a modern world? I have never heard any good proposals.

There are some alternatives.

Certificate pinning is probably the most widely known way to get a certificate out there without relying on live PKI. However, certificate pinning just shifts the burden of trust from runtime to install time, and puts an expiration date on every build of the program. It also doesn't work for any software that is meant to access more than a small handful of pre-determined sites.

Web-of-trust is a theoretical possibility, and is used for PGP-signed e-mail, but it's also a total mess that doesn't scale. Heck, the best way to check the PGP keys for a lot of signed mail is to go to an HTTPS website and thus rely on the CAs.

DNSSEC could be the basis for a CA-free world, but it hasn't achieved wide use. Also, if used in this way, it would just shift the burden of trust from CAs to DNS operators, and I'm not sure people really like those much better.

Certificate pinning is suicide in an environment where certificates expire in max 47 days. You'll have to rebuild and push your app at least that often and probably sync your devops with your certificate management.

Only if you pin a CA/Browser Forum-approved certificate. But you don't have to do that.

You can instead pin a self-signed or private CA-signed certificate, and then it can have the maximum lifetime you're comfortable with and that the software supports. A related option is to ship your app with a copy of your private CA certificate(s) and configure the HTTPS client to trust those in addition to, or instead of, the system-provided CAs.

I'm not sure how viable these approaches are on more locked-down platforms (like smartphones) and, even if they are viable today, whether they will remain viable in the future. It's also only good for full apps; anything that uses the system browser has to stick with the system CAs.

In an ideal world we could just trust people not to be malicious, and there wouldn't be any need to encrypt traffic at all.

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