- In my hand right now is an atomic clock.
Like the real kind with rubidium inside,
and installing it promises to make your computer
100 times faster.
That is,
if your computer happens to be a massive data center.
But seriously though, without a data center,
we've got it working here in our lab,
and based on what we've seen,
this could be the biggest leap forward
in computing this decade.
It doesn't sound like the biggest deal on the surface.
You know, nanosecond accurate time,
synchronized between every computer on a network.
So what right?
But so much computing overhead goes into compensating
for signal delays
that this could do everything from improving the efficiency
of live video broadcasts,
to dramatically reducing in game latency,
to enhancing online security.
And the craziest thing is that almost every device
from this computer to my phone
already has the necessary hardware to implement it.
All they need is an accurate pulse
from a card like this one,
and they're off to the races.
And we're going to show you guys how it works.
And we're going to tell you about our sponsor, Glasswire.
Are you lagging out while gaming?
Use Glasswire and see what apps are wasting your bandwidth
and causing your games to lag.
Get 25% off using offer code Linus at the link down below.
(upbeat music)
Highly precise timing
is a pretty mature technology at this point,
and it's already being used
in a number of critical applications, like power stations,
where a mismatch between the AC output
and the phase of the electrical grid could cause a big fire.
Or broadcasting where all the cameras need
to be synced up on the jumbotron to avoid tearing,
or for scientific research like at the large Hadron Collider
or our friends over at LIGO.
What is new about it is the affordability.
Now at $1,600,
most gamers would probably choose an RTX 3090,
or really almost anything else,
but in the data center, that is chump change,
and it's a fraction of what these solutions used to cost.
So here's our setup to show you guys why this is important
and just how good this technology is.
Inside this Nook 9 extreme is a rubidium atomic clock,
which synchronizes to GPS time periodically
using this antenna.
Oh, this one.
Not that it really needs to,
given that a clock like this should drift
about one second every 100 million years.
And then over here, this is another computer.
Now in the course of communicating with our first computer,
this one would normally attach timestamps
to every data packet to ensure that they are processed
and responded to in the correct order.
But we've got a big problem.
You see these two computers,
and probably the one you're using right now
are synchronized using the network time protocol or NTP.
And NTP was awesome,
back when it was created by David Mills back in the 1980s.
But to say that computers have gotten a little faster
and the internet has expanded since then
would be a gross understatement.
So look at this,
we've set each one of our computers
to output a timing pulse every second,
you can see right here, they're pretty close
within a few milliseconds of true time.
Oh, the blue one came unplugged. Hello?
Oh God, it broke a piece off of it.
Is it alive?
Please tell me we get signal main screen turn on.
- Yep. It's there.
- Oh, thank God.
Okay. We need tape.
- Do you want better tape? - No.
See the one in the back there
has actually managed to go,
each one of these lines represents a hundred milliseconds,
so a hundred, 200,
about 270 milliseconds ahead of true time,
which is this yellow mark right here.
While the green one has actually drifted
about 120 milliseconds back.
So the difference between them is about 400 milliseconds,
nearly half a second.
But while that might have been fine in 1980,
modern computers can perform literally millions
of calculations in that time,
which means that our speedy boy over here
ends up waiting around for the slower second machine.
Now watch this.
Da da da
control shift V,
da da da and da da da.
And it's time for an impromptu vlog.
This is Ahmad who is much smarter than us
and knows how this works
and he is remoted into our computer
to synchronize our nonsense here.
He likes hand-built this card, apparently.
What Ahmad is doing right now
is enabling the precision time protocol or PTP,
which should clamp things down
to be nearly a million times more accurate
than they were before.
How are your kids doing Ahmad?
I think I hear some kids in the background.
Getting lots of sleep, I bet. Right?
- [Ahmad] Yeah like everyone was like,
"oh you know, the moment he hits three months,
"he'll be good" it's not true.
(laughing)
- Not true.
I apologize for Alex bugging up
all of your carefully configured stuff.
- [Ahmad] No man, don't worry about it.
Alex is doing great.
- Did you just Alex is inbred?
- What? - Doing great.
- We think we know what happened.
The NIC that is behind our time card here
seems to be experiencing some kind
of thermal shutdown event.
Whose idea was it to do this with nooks?
Yay, I think we got it.
Okay. All right.
Awesome. Thank you.
Now that we're synced up,
we can zoom all the way in,
we're at a hundred milliseconds per line in our grid here,
we can go all the way down to one microsecond,
you can see the differences about 1.2 micro seconds.
That's about a thousand nanoseconds.
And when we're talking about time increments that small,
I mean, you can actually see
that this offset is very constant
between the two.
That's because that's the amount of time it actually takes
for the signal to pass through the FPGA,
through the PCI express bus.
So we can actually put an offset in
to have this thing dialed in exactly to GPS time.
But why does it matter?
I'm so glad you asked.
With two computers, honestly speaking,
it doesn't very much,
but if you're Facebook or Google
or let's say the entire internet,
making sure that every user gets the correct information
is very important.
I mean, you don't want someone's friendless to change
based on which server they connect to for instance, right?
So this means that every time a request is made
for some information,
checks need to be done
to ensure that the user is getting
the most current information.
But deciding of what the most current information is
can add a lot of overhead.
In the past if there was some kind of disagreement,
it was typically settled with a vote.
So the request goes out and all of the machines need
to decide what information is correct by voting.
When half of them machines say the information is correct,
it gets sent to the user.
This is easy enough if you just have a handful of machines,
but when you're dealing with a data center
where thousands or even millions of machines are involved,
I think you can see why having all of them vote
on every single user request isn't feasible.
So nowadays instead of a vote, a proposal is blasted out,
basically asking everyone,
Hey, is this the correct dog photo?
And if no one yells back,
no, it needs to have the text "Mondays",
then the photo gets sent to the user.
But the thing is that this method assumes
that all of the clocks are in sync in order to work.
And if they aren't, we can run into problems.
For example,
let's say that system A is two milliseconds behind true time
and system B is three milliseconds ahead of true time.
These are totally realistic number by the way,
as you guys saw.
If system B sends out a message and system A receives it
almost immediately, in less than that difference,
less than five milliseconds, system A will think
that it got a message from the future.
Now, thankfully,
the smart people at these massive data centers,
they have some kind of fancy code
to allow different machines to deal
with receiving timestamps data in the future, right?
No, they actually don't.
It turns out that the most foolproof solution
to this problem
is to just add a massive 20 millisecond delay
to every single request,
to ensure that every machine is always receiving data
that is timestamped from the past.
That is why adding an atomic clock to the mix
and getting the timing of every computer down
to this nanosecond scale of precision and accuracy, both
has such a profound performance impact.
In Facebook's case,
they were able to get 100 times the throughput
by eliminating that 20 millisecond delay.
What makes this incredibly cool though,
is that it can be used for way more
than helping Facebook efficiently sell your data
or a hedge fund make millions
with computerized transactions.
The entire project is open source
and can be implemented by anyone any way they would like.
Like if we wanted nanoseconds level order information
on LTTstore.com
so we know exactly who got a mouse pad
before they're sold out again.
One of the other ways
that this could affect you in the coming years
is competitive gaming.
By having highly accurate clocks
in every computer around the world,
packet timestamping would become a lot simpler
and especially more fair
for people who are geographically farther away
from the game server.
I could be playing battlefield for instance,
against someone in Korea,
and since the server would know
down to a few dozen nanoseconds who clicked first,
it would always accurately determine who got a headshot
and first going back to the load-out screen.
So Ahmad who hand-built our time card and sent it to us,
really wants to create a simpler version of this
that could be put into any NBME slot
to give gamers access to this technology.
And since there's a good chance
that the NIC in their computer already supports PTP,
it's not even that crazy of a goal in the longer term.
Hey, Bigfoot Network's dream of a gaming NIC
that actually does anything could finally come true.
- [Alex] Yeah.
- And implementing this super accurate timing
also has some really cool applications
for the fiber optic cables running beneath the ocean.
Roughly every 80 kilometers or so
there's a signal booster going across the ocean,
and if one of those goes down,
well, it shouldn't be a surprise to you
that accessing a cable run
that is several kilometers underwater
is pretty inconvenient.
But the thing is, before these repeaters give up the ghost,
they will usually start running slower,
and with accurate timing on either side,
you could actually figure out
that the signal is taking longer than expected
and figure out which repeater is beginning to fail.
From here, you could reduce the amount
of data going through it to extend the repeater's life
and schedule repairs.
Even more mind-boggling,
the undersea cables can be used
to detect gravitational waves.
You might remember our video
at the laser interferometer gravitational wave observatory
or LIGO where they use lasers
to super accurately measure changes
in the physical size of the earth
due to black holes colliding or something.
Well, LIGO is actually currently working
with the time appliance project
to get the timing between their three locations
to within a single clock cycle of their processors.
But by accurately measuring the time it takes
for light to cross the ocean,
you have suddenly turned the whole world
into a gravitational wave detector
instead of just a four-kilometer stretch of desert
in Washington state.
Accurate timing also has huge implications for security.
Like if you know that it always takes 10 milliseconds
for a message to be sent between two computers,
if there's some deviation,
like if someone tried to inject something
or sniff the packets,
you can just ignore the data
that didn't arrive when you expected it to.
And finally, PTP could have a huge impact
on streaming and live content.
Currently there's no real way
to verify the integrity of a stream.
You're basically just pushing out data
and counting on user complaints
to tell you that something is wrong with it.
With tighter clocks,
it should be possible to have much higher image quality
with fewer chances of corruption occurring along the way.
Although with these examples,
we are only scratching the surface of what can be done here.
The best part of all of this is
that there are probably loads of ways
that this tech will be used
that no one has thought of yet.
And since again, the whole project is open source,
anyone can implement it and change it however they want.
There really isn't much in the way
of this gaining widespread support.
Like I said before,
the tech is already built into a lot of computers
and is already being used by regular people
for things like 5G and GPS.
So make sure to hit, like,
if you enjoy this and spread the word.
Also we're considering implementing this in our office
to see if we get some kind of network performance benefit.
So make sure you're subscribed
so you don't miss that.
Are we really going to do that?
- [Alex] Maybe, I'm not sure either.
- What I am sure about is our sponsor.
Thanks to Squarespace for sponsoring this video.
If you need a website and don't know how to make it,
Squarespace makes it easy.
There's a wide selection of award-winning templates
and all of them are optimized for mobile,
so your website will look great on any device.
You can create members only content
for extra revenue, using Squarespace's members area.
You can grow and engage with your audience
with the powerful and easy to use email campaign system.
And if you ever need additional help,
Squarespace offers webinars, a full series of help guides,
or you can contact their 24/7 customer support
via live chat and email.
So don't wait.
Get started today by going to squarespace.com/ltt
where you can get 10% off your first purchase.
If you enjoyed this and you're looking
for more science-y videos from us,
check out our tour of LIGO,
the engineering that goes into the detection
of gravitational waves is truly mind bending.