Today’s Obituary was for David L. Mills, the inventor of the Network Time Protocol (NTP). He was one of the original ARPAnet engineers, the original US Government design experiment that became the Internet we now know and love. NTP was the solution to an important engineering problem of the nascent Internet, which was: every computer had its own clock, and time differences would cause data to go the wrong way or otherwise be misinterpreted on the new network. His invention of NTP synchronizes clocks on a variable-lag network to within a few milliseconds of each other. The Internet as we now know it and use it could not exist without this invention. He was known as “Father Time.”

Here is a bit about his invention. NTP is implemented on dedicated computers that work in strata (or layers), where stratum 0 is a set of atomic clocks (including some that orbit on satellites); stratum 1 are the computers directly wired to the atomic clocks; and stratas 2 and higher are connected via “laggy” networks in a downward cascade.

Each computer in the downward cascade performs elaborate calculations to average out the amount of time it takes information to reach it from the other NTP computers, using complex math to arrive at a very close approximation to the time reference of the atomic clocks at the top of the pyramid. Windows (the software that runs everything) automatically synchronizes to this time system, so that our robot overlords hum along nicely.

One interesting fact about the protocol is that all time originates at midnight January 1, 1900 and is represented in a 64 bit number by the number of seconds (32 bits) and fractions of a second (another 32 bits) since then. The largest number that can be represented in 32 bits is (of course you knew this) 4,294,967,296. This means that Internet clocks have been counting up the number of seconds from January 1900 to now, so that each second and fraction are unique. When the maximum value is reached, what happens? The number rolls over to zero, which would be bad. Very bad.

At this point I hope that you are all getting out your calculators to do the math to answer the question: when will this blow up?

It turns out to be at 12:00:00001 am February 7, 2036. Not that long from now.

You can’t really blame David Mills for this, since he came up with the protocol in 1981 to support a network of maybe 2 dozen computers that were strictly a government experiment. And in his defense, NTPv4, the current version, has two 64 bit elements, which ought to be fine. Really. As long as we can upgrade every computer on earth between now and then.

So, we are mourning the loss of one of the key inventors of the technology that is now the Internet, or “Interwebs” as I like to call it. What is the status of some of those others who helped Mills blaze this path? I’m glad you asked! Here is a reckoning of some of the most noteworthy:

Larry Roberts: Roberts headed up the ARPA net project initial implementation. He’s dead.

Paul Baran: One of the two scientists who independently came up with the idea of a packet network. It’s total genius! I think you just have to trust me on this one. He’s dead, too – in 2011. If you would like me to explain packet switching vs circuit switching, just ask, but be forewarned.

Bob Metcalfe and David Boggs: Metcalf came up with the ‘ethernet’ protocol, which enables computers to inexpensively and reliably connect to each other locally (in the same room or building) even when the wire or communication among them makes mistakes and sends the wrong number of volts. Metcalf is 80 and still kicking (he went on to found 3Com), but Boggs, his partner who was the implementing engineer of the first ethernet circuit, just died this year.

Vint Cerf and Bob Kahn: These two in 1974 invented what we now call TCP/IP (for this one, please just don’t ask, really), which allows apps to talk to each other reliably, even when the network is faulty and tries to introduce errors in the transmitted information, or delays or drops some of it. Cerf is 81 today; Kahn is 86.

Tim Berners-Lee: He is a British computer scientist who first came up with the idea for what we now call a “web page.” A lot of people think that this is the Internet. At 68, he is a youngster and still expresses his opinion when someone tries to ruin the Internet.

Paul Mockapetris: Paul was one of the original internet engineers at the University of Southern California in the ARPA days. When the network became too big to manually set each individual computer to a numerical address, he came up with the DNS idea. These are the “something.com” names that we are all familiar with. Born in 1948, he was a youngster at the time and is still with us.

Al Gore: Poor Mr. Gore is ridiculed by conservatives and climate change deniers who think that he claimed to have invented the Internet. He’s only 75, so we probably will have him to kick around for a while longer. In any event, he was a pioneer among US legislators who, in 1991, put together and passed a bill that funded much of the innovation during that time, including funding for the University of Illinois research group where…

Marc Andreessen invented the first web browser, called Mosaic. Internet Explorer, Edge, Chrome, Firefox, and many others are now available. Back then, though, Mosaic led the way. Because taxpayers paid for the staff and resources involved, it was offered free to anyone who downloaded it. Marc, born in 1971, is a youngster and is still with us. In fact, he’s a gazillionaire.

Bill Gates: Mr. Gates had nothing to do with the invention of any part of the internet, but he took a small piece of software (which he did not write) and turned it into one of the biggest and most profitable companies in the universe. Bill Gates represents the American dream. I just thought you would want to know.

That’s about it for David Mills and the invention of NTP, or the Network Time Protocol. So, what time is it, again?