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Network Latencies and Speed of Light

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Re: Network Latencies and Speed of Light

#41
post #9

Money is no object to HFT firms when it comes to reducing latency. A recent technique involves laying optic fiber cables with hollow interiors, so that the internal refraction of light spends more time in a vacuum and less time slowed down by the pesky glass medium.

very interesting!! Do you have a source for this? Would like to read up on it

Re: Network Latencies and Speed of Light

#42
Depending on how your Bond-villain vacuum tunnels and repeaters are set up, it's possible, i surmise, to create a tunnel way that can repeat without adding an interminable delay node or nodes. Imagine the One Way Valve Nikola Tesla patented, except with microwave repeaters shelled and pocketed into the sides of the tunnel passage instead of water-holding empty pockets.

Although I think that this is very nice, I always like to go to the "ultimate level" and consider what we would do if there was a way to send informative electrical signals using the earth as a resonator, and that idea chiefly brings me back to Wardenclyffe.

Did you know that the magnetic field of mars is weirdly shaped? It is only magnetic on the "Southern Half" of the ball that is Mars and has a slight gradient. So, assuming we can create some sort of information share that could function on the dynamic magnetic shielding of the earth, we'd have to rethink it for Mars, and any planet with a non uniform magnetic field from pole to pole.

Thanks a lot for your creativity. Keep writing, together we got this!

Re: Network Latencies and Speed of Light

#43
post #31

Earlier quoted context omitted.

Which is why the regulators really need to get sharper with them vs. what they are doing to the economy. They are front running, destroying value and spending the money on a whole load of tat - a massive case of misallocation of capital. They need to be shuttered.

HFT, or Bitcoin?

It's a shame people don't read the posted articles, they have so much good pondering material.

Re: Network Latencies and Speed of Light

#44
Very Naive Questions.

There are now fibre that has hollow core instead of light travelling through glass. Assuming we could do that in long distance, that is close to 0.98c, we should have +40% latency improvement right?

i.e Someday if we needed more capacity and this tech is available, we could lay this new fibre along side the same router as the current fibre. And enjoy some improved latency?

How much latency does each network hoop adds? 0.05ms?

How much latency does our own machine add? Are the 70ms actually all spent within the Network? Or would there be 0.5ms just coming from the Ethernet Controller, buffer or what ever?

Re: Network Latencies and Speed of Light

#45
post #42

Depending on how your Bond-villain vacuum tunnels and repeaters are set up, it's possible, i surmise, to create a tunnel way that can repeat without adding an interminable delay node or nodes. Imagine the One Way Valve Nikola Tesla patented, except with microwave repeaters shelled and pocketed into the sides of the tunnel passage instead of water-holding empty pockets. Although I think that this is very nice, I alway…

Don't forget neutrinos. They pass right through the earth, no tunnel needed.

Re: Network Latencies and Speed of Light

#46
post #45
post #42

Depending on how your Bond-villain vacuum tunnels and repeaters are set up, it's possible, i surmise, to create a tunnel way that can repeat without adding an interminable delay node or nodes. Imagine the One Way Valve Nikola Tesla patented, except with microwave repeaters shelled and pocketed into the sides of the tunnel passage instead of water-holding empty pockets. Although I think that this is very nice, I alway…

Don't forget neutrinos. They pass right through the earth, no tunnel needed.

Hmmmm can we encode information in neutrinos? I thought they were so few and far between it's difficult to reliably harness them.

Re: Network Latencies and Speed of Light

#47
post #46
post #45

Earlier quoted context omitted.

Don't forget neutrinos. They pass right through the earth, no tunnel needed.

Hmmmm can we encode information in neutrinos? I thought they were so few and far between it's difficult to reliably harness them.

But you can produce them artificially. https://arxiv.org/abs/1203.2847

Re: Network Latencies and Speed of Light

#48
post #41
post #9

Money is no object to HFT firms when it comes to reducing latency. A recent technique involves laying optic fiber cables with hollow interiors, so that the internal refraction of light spends more time in a vacuum and less time slowed down by the pesky glass medium.

very interesting!! Do you have a source for this? Would like to read up on it

May be of interest: https://meanderful.blogspot.com/2017/05/lines-radios-and-cab...

Re: Network Latencies and Speed of Light

#49

What about all the hops your signal has to take to make the round trip? Couldn’t those be optimized or sped up? Is copper latency really equivalent to fiber?

> Is copper latency really equivalent to fiber? Notwithstanding differences between specific types of cables and transceivers, yes, the rule of thumb is that they're roughly equivalent. The big advantages with fiber mostly come with being physically smaller for a given bandwidth (e.g. more bandwidth per square inch of conduit cross-section, more bandwidth per cable weight for vertical or suspended runs) and needing l…

An old style copper ladder line is ~0.95c and optical fibre is ~0.66c:

Old style, pre-coaxial, undersea cables may have been ~0.45. Newer coax is sometimes ~0.87c.

YMMV: https://meanderful.blogspot.com/2017/05/lines-radios-and-cab...

Re: Network Latencies and Speed of Light

#50
post #26

Earlier quoted context omitted.

Maybe the throughput could be increased using a bunch of MIMO antennas?

No, the throughput available at these frequencies is measured in bits per second.

PSK31 is 31 bps, but that's with ~100 Hz between channels. DXing is common in the 14 MHz band, so you could probably get to the megabits-per-second range before Physics (or the FCC) stops you.
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