

Lack of effective time signals could hamper IoT development - EGreg
http://www.nist.gov/pml/div688/timing-031915.cfm

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Animats
The actual paper: [1]

One of the strengths of the Internet is that it doesn't need tight time
synchronization to work. Analog TV did; all the network cameras and videotape
machines were synched to a time source in New York. Early digital telephony
did; all the time-division multiplexed lines were synched to a time source in
New Jersey.

As for real time, getting a response consistently within N milliseconds
doesn't require global time synchronization. A local clock is fine. Real time
operating systems such as QNX and VxWorks routinely do that. (The usual test:
hook up a square wave generator to a digital input. Have it trigger an
interrupt which activates a process. Have the process turn on a digital
output. Connect the digital input and output to a scope. Are there any
outliers, output signals that are delayed from the expected response time?
There shouldn't be, even if there are low-priority background jobs running.
Linux can't do that, but a true real time OS can.)

There's a demand for microsecond level clock synchronization in the financial
community, to measure the delays and record the order in high-frequency
trading transactions. And Google apparently uses tight time synchronization
for distributed database commit synchronization. But there's no reason to
require that outside single industry boundaries.

[1]
[http://nvlpubs.nist.gov/nistpubs/TechnicalNotes/NIST.TN.1867...](http://nvlpubs.nist.gov/nistpubs/TechnicalNotes/NIST.TN.1867.pdf)

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vvanders
Someone needs to tell them about dead-reckoning. These are things that have
been solved in game dev for quite a while.

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RIMR
Couldn't we just piggy-back off of GPS signals? They are, after all, an array
of orbiting atomic clocks...

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niche
This calls for a widely accepted "now" specification

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newobj
Bad news, there is no now.

[https://queue.acm.org/detail.cfm?id=2745385](https://queue.acm.org/detail.cfm?id=2745385)

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niche
Well now there is

