alt Hacker NewsI have never used DNSSEC and never really bothered implementing it, but do I understand it correctly that we took the decentralized platform DNS was and added a single-point-of-failure certificate layer on top of it which now breaks because the central organisation managing this certificate has an outage taking basically all domains with them?
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DNSSEC doesn't change the degree to which DNS is decentralized. It's always been hierarchical. In the absence of caching, every DNS query starts with a request to the root DNS servers. For foo.com or foo.de, you first need to query the root servers to determine the nameservers responsible for .com and .de. Then you contact the .com or .de servers to ask for the foo.com and foo.de nameservers. All DNSSEC does is add signatures to these responses, and adds public keys so you can authenticate responses the next level down.
A list of root nameserver IP addresses is included with every local recursive DNS resolver. The list changes, albeit slowly, over the years. With DNSSEC, this list also includes public keys of those root servers, which also rotate, slowly.
What you see here is decentralisation working. The issue is with the operator of the de TLD, and as such only that TLD is affected. DNS is not decentralised in such a way, that multiple organisations run the infrastructure of a TLD, those are always run by a single entity.(.com and .net are operated by Verisign)
So what the issue is, that the operator has, does not change the impact.
> which now breaks because the central organisation managing this certificate has an outage
The ".de" TLD is inherently managed by a single organization, and things wouldn't be much better if its nameservers went down. Some of the records would be cached by downstream resolvers, but not all of them, and not for very long.
> we took the decentralized platform DNS was and added a single-point-of-failure certificate layer on top of it
DNSSEC actually makes DNS more decentralized: without DNSSEC, the only way to guarantee a trustworthy response is to directly ask the authoritative nameservers. But with DNSSEC, you can query third-party caching resolvers and still be able to trust the response because only a legitimate answer will have a valid signature.
Similarly, without DNSSEC, a domain owner needs to absolutely trust its authoritative nameservers, since they can trivially forge trusted results. But with DNSSEC, you don't need to trust your authoritative nameservers nearly as much [0], meaning that you can safely host some of them with third-parties.
[0]: https://news.ycombinator.com/item?id=47409728