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Comment by vlovich123 | Hacker News Reader

I wonder if the only change that needs to happen is that applications driving a significant amount of traffic (i.e. Chrome) & DNS owners of other domains need to start bearing the costs here. Then we wouldn't be dealing with cost externalities & tragedy of the commons. On the other hand, introduce revenue streams & you start focusing on optimizing the revenue stream instead of solving the problem.

I wonder if there's a different way to make the costs felt that isn't directly revenue to align incentives. Like slow down or fail queries for zones who's authoritative servers don't implement the features needed to keep scaling under control. Then make sure that there's revenue to the root servers from non-root servers based on load so that costs are tracked & managed.

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Just let google run some of the roots - I'm serious. For all the whining about bandwidth and traffic, this issue is so small on the scale of google (which includes youtube) and netflix traffic flows it's hard to even imagine.

Their secondary resolvers run at huge volumes, everything from 8.8.8.8 to the dns for their mail and other web properties.

The problem is it does not help to have one or two fast roots. The root server model only really works when the roots each have similar capacity.

A root is not one static machine. Google can serve 1/3 of traffic for all routes, AWS could do the same.

I don't think folks realize how SMALL the root dns traffic is. Youtube / netflix / amazon prime video are just orders and orders of magnitude more demanding in terms of bandwidth - every second they are pumping MULTIPLE HD streams to millions of folks. They measure bandwidth terrabits per second. Even at 30 frames per second, we are talking incredible bandwidth.

DNS responses should be 1K or less (often .5K). About 40 netflix viewers at their top quality use the same bandwidth? Netflix has far more than 40 users.

You think the root operators should just delegate part of the traffic of all letters' VIPs to google and amazon? It's not crazy, but it would mean the entire root would have a shared-fate failure mode.

I don't understand. What's the failure mode you're thinking of?

Someone at Google pushes yet another invalid config of death, taking out their global network and, with this proposal, also taking down 1/3rd of all DNS root capacity.

You could easily 3x provision root dns (or more).

I'm just pointing out that for all the complaining about google efforts to block domain jacking (which was endemic before they started their efforts) scaling the root is doable, and if the existing maintainers are too incompetent to scale it then maybe others should be allowed to.

I mean, how do they handle denial of service attacks which are going to be orders of magnitude higher in volume?

The logic here is so warped.

https://www.digitalinformationworld.com/2020/08/a-major-bug-...

Rather than the solution being to allow for domain hijacking by turning off the redirect detectore, how about verisign, which kicked this whole thing off recently AND way back with their "sitefinder" garbage get a clue and either propose another solution to domain jacking or scale the root a bit.

There already is precedence for this. Cloudflare provides a huge chunk of F-root servers.

https://blog.cloudflare.com/f-root/

Yeah, and it makes perfect sense for these big tech cos to run all or some of one root letter. But it violates the spirit of resilience to have one company participate in multiple letters.

Like Verisign does, ne? (-:

You've conflated the proxy DNS servers, that do grunt work of query resolution (or forward to other proxies that do), with the content DNS servers. It is not the content DNS servers that are causing the scaling problems, it is the proxy DNS servers, and the DNS clients and applications softwares that drive them.

* http://jdebp.uk./FGA/dns-server-roles.html

The change that needs to happen is the thing that most people nowadays tell one first, that this paper in contrast leaves all of the way to the end: run your own content DNS server(s) for the root, on your own LAN or Intranet. It's fairly simple to do, and it's an idea that has been around for over two decades, now.

* https://news.ycombinator.com/item?id=24277855

* https://news.ycombinator.com/item?id=19526108

* http://cr.yp.to/dnsroot.html (dates back to 2001)

* https://news.ycombinator.com/item?id=24280536 et al.

It takes a long time in the DNS world for such grassroots ideas to percolate to the level that they get circulated by corporate officers. This article is, for example, still propounding that every resolving proxy DNS server works like ISC's BIND, and has a "priming query". This is untrue in reality, and is one of the differences between BIND and some of the softwares (e.g. dnscache and MaraDNS) that came along to replace it a couple of decades ago.

* https://maradns.samiam.org/faq.html#roothints

Similarly the argument that Google should use a subdomain, presented in this article without any counterpoint at all, has long since been countered by pointing out that this makes the malicious actors' lives easier; as conditional forwarding and split-horizon DNS service, which are well-known things, would then make it easier to fool Google Chrome. And there have been other counterarguments made, years ago.

* https://news.ycombinator.com/item?id=3609498 (yes, 2012)

I think your terms are incorrect. Proxy queries in your context are referred to as recursive and content is authoritative.

These aren't types of query, they are types of server. viovich123 was talking about content DNS servers that cause the scaling problems, and penalizing the people who run them. But it is the proxy DNS servers, and the DNS clients and applications softwares that drive them, that are the cause here.

The terms are correct, and are derived from HTTP. You aren't grasping them correctly.

These terms are not listed in RFC 7719 “DNS Terminology”.

> You aren’t grasping them correctly.

I find this to be quite rude.

I've never heard those terms only recursive / resolver and authoritative. Who uses content and proxy?

> The terms are correct, and are derived from HTTP. You aren't grasping them correctly.

This, I think, is the source of the problem. DNS servers have their own terminology that pre-dates HTTP. The servers that take/do lookup requests and cache them are known as recursive servers. Yes, they act similarly to HTTP caching proxies, but that's not how they are referred to. These make up the vast majority of DNS servers.

The other type is authoritative, which is called that as it is the 'athoritative'source of truth for some domain's DNS data. Where the root servers look it up to feed into the system. These would be akin to your basic HTTP servers, but again the terminology is different.

This is the source of the problem. People don't understand the DNS terminology. Very few people indeed get "resolver" right, for example, and they only then end up confusing the rather larger number of people who get it quite wrong. Similarly, "authoritative" confuses people when they have to try to understand why it isn't actually the same as an "authoritative answer". Whereas they do understand the idea of DNS records being content, that is published by content servers.

Hence why many years ago I took to explaining DNS using HTTP terminology. It works quite well.

> Hence why many years ago I took to explaining DNS using HTTP terminology. It works quite well.

That is the source of your own confusion. There will be no memorial for you on the hill that you're dying on.

I can see where you're coming from, as it does work as a close metaphor and people are generally more familiar with HTTP. I think the disconnect is that while that is a good way to relate it, seems like teaching the correct terminology along with the basic idea is generally better as it also gives them the tools (eg. as search criteria) to research it more themselves.

Long experience shows that it doesn't. It just adds layers of obfuscation to the subject. You spend all of the time explaining what a "resolver" is, for starters, and then have to explain how that model then doesn't really match how the softwares fit together on their operating system and LAN, because it was intended to be an operating system neutral model. And then you get to explain that almost no-one will understand you correctly if you use the term properly.

Whereas explain to them that it's a form of publication, from content servers through proxies to client libraries in applications, like HTTP, and it generally clicks what part of the overall system talks to what other parts. People have some absurd models of how things work, from ISPs talking to ISPs to relays along chains of content servers.

Explaining that it's actually like HTTP gets people using the correct mental model, and matches how the softwares in reality fit together. There really is a DNS client library, and it has a name such as (for example) libresolv. There really is a proxy DNS server, and one can point to a specific process running its program, again with names (dnscache, pdns-recursor, et al.), to its back-end and front-end traffic, and to whether it is configured to forward or to resolve. There really are content DNS servers, again with nameable programs (nsd, tinydns, walldns, pdns_server, et al.), with specific locations, and with content sources that one can point to.

The fact that RFC 7719 exists should tell one something, even if it weren't spelled out in its introduction that the RFC terminology is confusing, contradictory, and going to change wholesale "real soon now".

Here's a mental exercise:

Configure your machine with 1.1.1.1 in /etc/resolv.conf. The RFCs, including RFC 7719, tell you both that your "resolver" is the program that does the entire job of "resolution" and that it is located on the same machine as the program requesting the lookups. You have a DNS client library locally, linked into your applications, that is talking to a resolving proxy DNS server running on a machine operated by Cloudflare. The resolving proxy DNS server is doing all of the grunt work of query resolution, retrieving content from content DNS servers with back-end transactions, and Cloudflare's machine is where its front-end and back-end are. It's simple to explain that way. Now point to your "resolver". Then further try explaining it to someone else. Then try explaining that Cloudflare's server is a DNS server, but not a "name server". See what happens when you tell them that for an explanation of "name server" they just need to use RFC 7719 to "research it more".

> These aren't types of query, they are types of server

Actually, they're both a type of server and a type of query.

> viovich123 was talking about content DNS servers

DNS has nothing to do with content, it's name to address resolution.

No, content and proxy are types of server. There's no such thing as a "content query" nor a "proxy query".

And DNS very much is content. The content is a whole bunch of resource record sets. Published by content servers, much as in HTTP. And it isn't all name to address stuff.

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