Dave Mills has died | Hacker News Reader

Dave Mills has died

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731 pointstodsacerdoti79 comments

I’ve recently gotten very into NTP with GPS and PPS as a fun personal project. Just a couple weeks ago I was reading about him on Wikipedia and I could relate to this quote (as no one else I’ve talked to about PPS has shown any interest):

> he enjoyed working on synchronized time because no one else was working on it, giving him his own "little fief"

Debian recently switched to NTPSec, and I was happy to see how familiar their website style was to the main NTP site. In the FAQ I found:

> [Q] Why do these web pages look so 1990s

> [A] Because that simple look is good for people with visual impairments, and as a tribute to Dr. David Mills, the original architect of NTP who is himself visually impaired. Dr. Mills has very particular ideas about Web visuals, and this site is carefully styled to resemble his NTP documentation pages.

I’ve never had an opportunity to meet him, but he has certainly made a positive impact on my life. Rest in peace Dr. Mills.

Same here, getting into PTP, you end up studying a lot about timing on computers, and Dr. Mills is one of the main players in building up modern timing foundations! RIP, and thanks for all your contributions!

He really was. I remember encountering him on comp.protocols.time.ntp two decades ago and the breath of knowledge he had on computers keeping time was astounding, both at the time, and now that I look back at it.

here's that page

https://www.ntpsec.org/FAQ.html

I understand (and endorse) simplicity of design, but that page doesn't even have a link back to the home page. They've gone too far past accessibility into creating a less-accessible page...

Note well: all accessibility decisions are trade-offs. Do you need a link to the home page if you have a perfectly-good address bar? Some people do; for others, it's a nuisance. If someone with particular accessibility needs has designed a website, and diverged from usual practices, I tend to assume they had a reason for it. (That isn't to say I'll naïvely copy it. Usually I'll ask, but that's no longer possible in this case.) Imo, they should have a link (either <a> or <link>) with rel="up", so the browser's Up button works.

I think you miss the point. This page was linked to you from somewhere. “Home” in that context is back where you came from, I.e. the back button. Finding this page could have come from anywhere and sites don’t have to have pages keep you in their domain. That’s not how the web used to work. Nowadays everyone has their own “site” and it’s a much different eco system from decades ago.

The first website ever, at CERN [1], is not very consistent about this. Some pages [2] do link "home", but don't use this term: in this particular case, a link to "the WWW project" is given in the first sentence. Some [3] do not.

[1] http://info.cern.ch/hypertext/WWW/TheProject.html

[2] http://info.cern.ch/hypertext/WWW/Status.html

[3] http://info.cern.ch/hypertext/WWW/Helping.html

> “Home” in that context is back where you came from, I.e. the back button.

...No, that would be "back", not "home". Those aren't interchangeable terms unless you are coming from a (or your browser's) home page.

Anyway, this page is an FAQ about the site itself. It is not a standalone document. Without the context of the rest of the site, it has no meaning or value. There is no better use case for intra-site links than a page written entirely about content on other parts of the site.

Meh, it's common to want to navigate to the root of a domain to find more information if you've been linked to a subpage that may lack some useful context. You can of course edit the URL by hand, but that's less convenient. Intra-site navigation links have a purpose.

(Perhaps on another timeline browsers would have had an "up" button in addition to "back" and "forward" like filesystem browsers do, but that did not happen. Even <link rel> doesn't have an "up" option, though it does have "prev" and "next" – not that anyone uses <link> for anything but rel="stylesheet" and maybe rel="alternate". EDIT – rel="up" used to exist but was dropped from HTML5 with no reason given. I presume it's nevertheless supported by browsers and eg. screenreaders.)

And if you haven't looked at it yet, you should probably look at Network Time Security (NTS). https://www.netnod.se/knowledge-base/What-is-Network-Time-Se...

Which NTP site are you referring to? I’m keen to check out some examples.

ntpsec.org

https://ntpsec.org/accomplishments.html is a good read for some fun insight in to what it takes to modernise a 1990s pre-git codebase and build chain.

The New Yorker published a piece on Network Time Protocol a little more than a year ago[0] - highly recommend it to anyone interested in how the internet works.

RIP Dave, and thank you.

[0] https://www.newyorker.com/tech/annals-of-technology/the-thor...

Discussed on HN back then:

https://news.ycombinator.com/item?id=33131195 (41 comments)

This is sad news. I worked (a little bit) with him when I added the adjtime system call to linux back in the 0.99 days.... He built stuff that worked and is run everywhere. That is a great legacy. He will be remembered.

Just curious: what is 0.99 in this context?

Almost sure this is the linux kernel version.

According to wikipedia, this is circa '92 era https://en.wikipedia.org/wiki/Linux_kernel_version_history

Yes -- that is right. Back in those days, you could build the linux kernel from scratch on a laptop with 16MB of memory! I used to commute (on a weekly basis) from Boston to NYC, and you could build and boot and test a kernel between taking off from Logan airport and landing in La Guardia! I can't recall the vendor of the laptop that I used, and the internet is indicating that maybe the 16MB was an overestimate.

I think that the adjtime call went in in Linux 0.99pl15 (there were different numbering conventions back then).

I first got Linux (Slackware) around about that time. I had a desktop with 4MB (later with 8), so I'd say 16MB in a laptop would've probably not been right too.

I remember the interesting "plXX" patch numbers too.

16MB of memory in 1992? Boy oh boy, ain't you the most spoiled kid ever? When I got 4MB in 1994 I though I caught God's foot.

Dave Mills was helpful to me as a student. I did some research into NTP in 1999. I knew a little bit about it but not a lot and I said and did a lot of brash things (including sending query packets to every NTP server on the Internet). In response to my random poorly written mailing list and questions Dave answered me and gave me some useful pointers. I felt a little like I was talking to a celebrity.

NTP is a remarkable technology. Getting millisecond synchronization out of megahertz computers and barely-megabit computers was not easy. Honestly I'm not sure I would have thought it was even possible until I read the papers explaining how it worked. And Mills didn't just make it on his own, he helped create a small community of timekeeping experts on the Internet that persists to this day.

I at first read this as him being your student and started wondering how long ago your 100th birthday was.

I hadn't heard from him in decades, but I knew him back when TCP/IP was starting up and his Fuzzballs were used as routers.

John Nagle

Fuzzballs?

https://en.wikipedia.org/wiki/Fuzzball_router

The Fuzzball paper: https://dl.acm.org/doi/pdf/10.1145/52324.52337

Are you John Nagle, of the Nagle algorithm?

https://news.ycombinator.com/item?id=9048947

I met Dave a few times in the 90s, first when he was visiting Peter Kirstein at UCL. I'd taken network time as simple to get right until that evening chatting with him in the pub. Fascinating discussion of what can go wrong - and a lot of patience with a young networking researcher who didn't know what he was talking about. I've had a high respect for the attention to detail he embedded in NTP ever since. RIP.

Took a class of his at University of Delaware around the turn of the century. He was a great professor that clearly had a love for the subject.

NTP was much more complex and nerdy than some of the other trivial protocol RFCs, especially by v3 (https://www.rfc-editor.org/rfc/rfc1305), which was the first one I read. A legend; RIP

I had professor Mills in the mid 90s. He knowledge and application of hardware and software was truly impressive. A true hacker (In the finest sense of the word). RIP

Same, I took several of his classes in the late 90’s at UD. I remember him fondly. RIP

If someone is interested, here is the Reference and Implementation Guide of the latest NTP version (2006, was revised in 2010), written by Dave Mills: https://www.eecis.udel.edu/~mills/database/reports/ntp4/ntp4...

Quite well written, in my opinion.

His talk on the early internet https://youtu.be/08jBmCvxkv4?feature=shared

He influenced my career as much as Dennis and Ken did.

Our "nanokernel" paper brought NTP into the nanosecond domain and gave FreeBSD "timecounters".

But our true shared passion was Loran-C

Dave even invented the 16-pulse "tactical Loran-C" during the Vietnam War.

I borrowed his ISA card Loran-C receiver (serial #1 & only) and later I built two generations of SDR receivers, and he was so proud when I showed him this dancing pulse received with a cheap ARM chip:

https://phk.freebsd.dk/AducLoran/animation2.gif

And boy was he pissed when USA shut down Loran-C, he really loved his "loudenboomers"

RIP

What is the difference between Loran-C and tactical Loran-C? I googled "loran-c vs tactical loran-c" but did not come up anything. Thanks.

Tactical Loran, also known as "Loran-D" was a concept Dave was involved in during the Korea war. There's a pdf about it somewhere on the web.

Remember: This is way before GPS, so pilots could not just look at an instrument and know where their plane was, and many planes, both civil and military would regularly get lost (in the meaning: loose track of where they were).

In friendly skies you could have your own Loran-C, but you couldn't expect the enemy to provide that for you, so "tactical" meant that you could rig up a naviation chain where you needed it, in a matter of days.

(In the end both USSR and China set up Loran-C chains, some of them operating jointly with the US chains, and today the Rusian "Chayka" and possibly the chinese chains are the only ones left.)

So tactical Loran was basically Loran-C transmitters in containers or trucks, and because they would be much weaker than real Loran-C, being both power constrained and having much smaller antenna, they used a 16 pulse code instead of an 8/9 pulse code.

Loran-C&D is spread-spectrum transmission, but decades before the theory was fleshed out, but it was well understood that a longer pattern would improve S/N.

But Loran-C/D was just one of many DoD radionav systems that project 621B (=GPS) was supposed to kill, and eventually did kill.

More about him: https://en.wikipedia.org/wiki/David_L._Mills

I just imagine all the ntp daemons becoming falsetickers for a moment

I contributed to NTP.

The manufacturers of the cheap device I cajoled within ntpd into generating more than an order of magnitude more precision than they expected offered me decent money to write them a commercial driver. But I pointed out that they could just steer their customers towards NTP for most platforms and it was already done!

We get the news from Vint Cerf himself.

Thanks Dave, rest in peace.

Giants. Seriously, I get this vibe when looking at all these people, the early internet culture. Sometimes I feel as if I was there... or rather really wanted to be.

Sad day for the Internet, Rest in Peace David L. Mills , and that time keeps going on forever to you and your energy to be felt across time and space.

I'm sure the artifacts of your work will never be forgotten.

----

On a sidenote

Last year I had a chat with one of the members of the early Web and we understood there's a serious issue of knowledge transfer to future web devs generations.

Few people reads books, and even if they do, the books written by technical people are not pedagogical enough as to allow the reader to capture the Tacit Knowledge and experience from the author as to be able to reproduce new ideas.

We are LOSING fundamental knowledge of the internet for every mind who dies. If you think that mailing lists, web archives, books and blog posts are enough then you're being naive.

At some point nobody will understand how the Web works. The curve where the Web is going is not pretty.

This is extremely troubling to me and I'm trying on the sidelines to have some sort of way to run Tacit Knowledge extraction from those ppl. Known techniques are ACTA and CTA (Advanced Cognitive Task Analysis and Cognitive Task Analysis).

If you have any other idea, please let me know.

> At some point nobody will understand how the Web works

Sorry to be blunt; but that is absolute weapons grade nonsense on multiple levels.

First, we aren't losing any knowledge on how the internet works; at least, as far as I'm aware. Can you please explain what you mean? What knowledge have we lost? Are we unable to write networking stacks because some greybeards aged out?

Secondly, If you think the guys who wrote the first C compilers and implemented NTP have much of an idea how the 'modern internet' works even today (outside of what you can learn reading beej's guide), you're wrong. I'd be happy to be proven wrong, again, but I struggle to see how folks like these would be useful on the team who implements, for example, the distributed caching algorithms used by Akamai..

I get your sentiment, it's definitely sad and a 'passing of the guard' sort of feeling when the first engineers pass on, and for sure, they know a lot about their domains. But lamenting that 'nobody will understand how the web works' because no one cares about ISC bind's implementation anymore is kind of bonkers.

I don't think we're losing knowledge of how the Internet works, but we're almost certainly losing knowledge of why it was done that way. I remember Bob Braden saying (and I paraphrase):

"When we designed the early Internet, we had a huge blank space to work in, and we agonized over what the best way to do things would be. Ever since, people have been filling in all the other parts of that space."

This was 20 years ago, but he's probably even more correct today. Of course they didn't get everything right by a longshot, but we're definitely losing the rationale for why things were done the way they were. As a result, it's quite common to stumble into old problems that had been engineered around before.

I don't think we're losing the macro "why" at all. We may be losing the wisdom of the path they walked to get to their design, which is certainly very valuable from a pedagogical and historical perspective.

I think that's the point, isn't it? That we're in danger of losing a lot of important history & context that underpinned the "macro"

Yes, that's the whole point I was trying to make. Without history of the why we tend to make the same mistakes all over again. Extracting the why is much more difficult than simply writing a book, there are psychological prompts to do that

I read it more as "losing knowledge of why things are the way they are today" i.e. the earlier technical context & nuance that caused things to evolve in the way they have.

Nice example from a link in this thread is a Dr. Mill's talk at udel: https://youtu.be/08jBmCvxkv4?feature=shared It's packed with interesting context and history stretching back to 1968

You are correct, that's what I meant. Understanding the why allows us to evolve ina. direction ina. way that's educated instead of making bad decisions and committing mistakes that shouldn't have been made

I see you've never met my coworkers: Akamai does employ a number of people with very long experience in the IETF world.

There is quite a bit of bad ideas the people pop up to propose time and time again, because they don't get why the net looks the way it does or the constraints on evolution. The old timers also understand when things have changed enough to justify new things.

W3C and IETF both have a paucity of early or middle career participants. So where are all these people who understand how it works? Not making more standards to solve some real problems.

I didn't speak with them, so I can't verify if "There is quite a bit of bad ideas the people pop up to propose time and time again". I need to verify why they are bad and why they're proposing. Before concluding they're bad you need to understand why. Many ideas are bad, but what I'm saying is that there's a few people like Roy Fielding, Tim Berners Lee, Mike Amundsen, & other that I don't remember their names, that actually have GREAT ideas, only that newbiew engineers with title of "senior" don't understand. Not saying it's your case, just saying there's no way to verify so I can't "explain" to you the effect you're observing.

The Powersharing Series is a great first-person resource for the 1980s PC era: https://www.thepowersharingseries.com/

What can we do to stop this erosion of knowledge?

Reach out to folks who are in the last chapter of their life and collect the knowledge, Story Corps [1] meets ArchiveTeam. Interview them, create or add to their Wikipedia page and upload other artifacts to the Internet Archive.

[1] https://storycorps.org/

That and CTA/ACTA. Extract Their Tacot Knowledge using those techniques and convert them into simulations that can be use to mentor/teach new engineers with the WHY they did what they did by putting them in their actual shows.

Nobody has done that as far as I know

Truly a sad event. I never met him but found his work to be so well explained, even in writing and practice. Wrote him an email once and got an informative and kind response. Highly recommend folks to read his website to get to know how to write well and convey complexity in detail, as a story.

If I could save time in a protocol

The first thing that I'd like to do

Is to save every day

'Til eternity passes away

Just to spend them with you

I’ve never looked at NTP so I followed a link here to RFC 1305. I found this gem of humility.

> Note that since some time in 1968 the most significant bit (bit 0 of the integer part) has been set and that the 64-bit field will overflow some time in 2036. Should NTP be in use in 2036, some external means will be necessary to qualify time relative to 1900 and time relative to 2036

The 2036 problem is fixed in RFC 5905 as there is no doubt it will be needed.

No NTP means no crypto.

Most of crypto cyphers nowadays relies on having both computers in sync clock wise.

I learned it the hard way with openwrt routers disconnected from the internet.

Not exactly, timestamps only commonly matter for handling certificate expiry, and you'll still be fine if you're a few minutes out.

I had the opportunity to meet him at UD earlier last year, very bright man who was still actively working on many things.

FTR, the black bar atop the site header (as of Fri 01/19 at 10p ET) is intended to honor Dave Mills. See also https://news.ycombinator.com/item?id=39063870

I discovered NTP through Computerphile & Tom Scott.

What a great invention.

I enjoyed his writeups about the fuzzballs back in the day, I learned a lot and had fun doing it.

I took his class @ University of Delaware in 2002.

R.I.P Professor Mills.

Extraordinary wizards. Founding fathers. True legends.

RIP

Thank you Dave! Rest in peace

Was there no black bar? Or did I miss it?

There should be. Mods are asleep.

Another black ribbon day for HN. RIP Dr Mills. The internet wouldn’t be the same were it not for you.

There should be one for Dave Mills. Another legend that deserves recognition for the foundations of the internet that hundreds of millions use today.

RIP Dave Mills.

Ought to be a black ribbon for Dave Mills...

They tried to apply the ribbon for a time, but the server's clock was wrong.

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