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What the damaged Svalbard cable looked like

nrk.no

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Re: What the damaged Svalbard cable looked like

#241

Earlier quoted context omitted.

Related, I was struck by a comment made by the respiratory specialist doctor Martin Tobin, during the George Floyd murder court case. He said less than 10% of smokers actually go on to get 'issues'. He was pushing back on the line that as a smoker, George Floyd was more prone to react badly to 'having a knee on his windpipe...' you know the rest. I did rewind and listen again then look up what he was saying and indee…

For anyone curious, I found the relevant sentence. An astonishingly counterintuitive almost throwaway remark by a world's expert sent me on a deep dive on what else can and does cause lung problems. Dr Martin Tobin says it at 3h 02m 40s... https://www.c-span.org/video/?510467-1/derek-chauvin-trial-d...

He said that less than 10% of smokers HAVE lung issues, not “eventually get” lung issues. Big, big difference.

Re: What the damaged Svalbard cable looked like

#242
post #239
post #175

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> understand the details… really understand everything That’s two different standards, and only relevant if either of them was a significant percentage of total population. Most people don’t even understand why a refrigerator door gets briefly stuck after you close it. It’s practically a magic box that gets cold which is perhaps why they fall for conspiracy theories so readily, any explanation is equally plausible. A…

One way to convince yourself that a fridge is simpler than a 5G cell system is to look at the science history behind them. The heap pump, the core concept behind a fridge, goes back to 1748 (Cullen). Radio goes back to Maxwell (circa. 1864) and Hertz (1886). Basically at the time that Radio was invented/discovered refrigeration along the lines of the modern fridge was well understood. The first cellphone was invented…

Longer history can also imply complexity. A 2024 Honda Civic is way more complicated than a Model T.

Though ultimately yea a smartphone extremely complex. I’m just saying being able to have a high level understanding is very different than knowing how to maintain or design something.

Re: What the damaged Svalbard cable looked like

#243

Earlier quoted context omitted.

TL;DR of the court cases: the fisherman was guilty of damages to the tune of $1.2M, and his insurance cover was voided because his act was so reckless. Funnily enough, the cable owners (Telus) tried to thread the needle of making the owner liable, but not so badly that insurance wouldn't pay for it. The judge didn't buy this, and obviously a sole operator crab boat can't pay over a million in damages (although he did…

Makes you wonder if those cables should (can) be insured against such problems instead of relying on a craber's insurance.

Telus’ insurance would have a deductible, they can’t claim for every little thing

Re: What the damaged Svalbard cable looked like

#244

Earlier quoted context omitted.

> The Shannon limit is constant if you assume reasonable but idealized SNR values for the medium The Shannon limit is changed by changing technology over the medium, not the other way around. If you signal with light on/off pulses, you get one limit. If you add polarization tricks (using different physical properties and tech), you get another limit. As you add QAM and a zillion other tricks, you get another channel…

There is also a technology-independent Shannon limit for a cable. You can calculate Shannon limits based on the bandwidth and noise of your specific fiber-optic transceivers, which can improve, but you can also calculate one based on the cable itself. The Shannon limit already accounts for any number of channels and any level of QAM.

I just gave you a paper showing that is not the case. I even provided the quote.

There is no inherent limit from physics, only from engineering. History provides ample evidence were a given medium had it's "Shannon Limit" broken via new signaling methods over the same medium. The terms you used, "bandwidth" and "noise" are technological, not physical. "Bandwidth" increases each time we invent better methods to pack and decode it. Most of the old concepts are based on old Fourier Analysis, whereas a better modern framework is wavelets or even their successors. Fourier is a very simple way to think of signals, missing plenty of useful things, which is exactly what led to the development of wavelets, to enable more powerful signal analysis.

Note in particular there is no single "bandwidth" when dealing with photonics, since photons can be physically stacked arbitrarily without interference. Simply google for breakthroughs in photonics bandwidth to see decades of advances beyond what was previously thought to be "the bandwidth".

The Shannon limit is a *model* of the system. That model is necessarily incomplete, since there increasingly advanced technology. Those models almost always use simplifications to make the math tractable, such as gaussian noise, independent errors, and a host of other things that are not true physically. Even the concept of noise requires either a non=physical abstraction to math or some details of the engineering used to measure it. Simply saying there "is gaussian noise" is a gross model used to simplify math. It is non-physical.

A simple example that leveraging quantum has created a new field of quantum shannon theory, which has better bounds. Under shannon's theory and his understanding of information, quantum key distribution would not be possible, yet it is, and companies have offered commercial versions for 20+ years. I would not be surprised if more and more pieces of physics not currently used for communication get used in the future, changing the "limits" again and again.

Before MIMO transmission, single channel over the same medium had a shannon limit. MIMO surpassed it. Many channels, especially where light is used, allow stacking more and more information into the same medium, subject to technology ability to decode, which is an engineering feat, not a physical one.

The world of information theory has moved past shannon, just like orbital mechanics moved past Newton. Both Newton and Shannon have uses, but they're not valid for modern techniques.

Two of many such changes are compressed sensing, which was a major discovery, that routinely beats Shannon-Nyquist sampling theory, and the discovery of what is called generalized sampling developed around 2000-2010 (and still making it's way through image processing). Both are fundamental theory changes that allowed breaking previous "limits".

So please read the paper, and if you claim there is still some inherent limit, publish the paper countering the one above.

Re: What the damaged Svalbard cable looked like

#245

Earlier quoted context omitted.

> The Shannon limit is constant if you assume reasonable but idealized SNR values for the medium The Shannon limit is changed by changing technology over the medium, not the other way around. If you signal with light on/off pulses, you get one limit. If you add polarization tricks (using different physical properties and tech), you get another limit. As you add QAM and a zillion other tricks, you get another channel…

There is also a technology-independent Shannon limit for a cable. You can calculate Shannon limits based on the bandwidth and noise of your specific fiber-optic transceivers, which can improve, but you can also calculate one based on the cable itself. The Shannon limit already accounts for any number of channels and any level of QAM.

Ah, here's but two interesting and well cited papers regarding an optical "shannon limit", both published in IEEE Journal of Lightwave Technology.

The old idea of a "Shannon Limit" has been split into many types, including linear (old tech) and non-linear (using more modern tech). Both these papers address the non-linear limit (which is not a limit, as both papers show, but more of an artfact of modern tech):

[1] "Approaching the non-linear Shannon Limit" : From the abstract "We also discuss the techniques which are promising to *increase* and/or approach the information capacity limit."

[2] "Scope and Limitations of the Nonlinear Shannon Limit" : "It is shown that this is a limit (if at all) holding only for conventional detection strategies. Indeed, it should only be considered as a limit to the information rate that can be achieved with a given modulation/detection scheme"

These are extensively cited, so use google scholar and read up to see that there is no "Shannon Limit" except for a particular channel technology. The concept has been split into a million directions depending on the underlying technology, each with a different value for "Shannon Limit".

[1] https://ieeexplore.ieee.org/abstract/document/5210179 [2] https://ieeexplore.ieee.org/abstract/document/7637002

Re: What the damaged Svalbard cable looked like

#246

Earlier quoted context omitted.

That's a good reason to think it wasn't Ukraine not that it was. They're in open war with Russia, are openly attacking their resource infrastructure, and are frequently posting excellent high quality footage of it. Taking out the gas pipeline and then not using the attack for propaganda doesn't fit either their situation or their actions.

The pipeline had the additional complication that it was supplying heating fuel to Europe. Bragging about it to the Germans would have probably been a bad idea.

That's the thing though, at the time it wasn't supplying gas. Gazprom said it was having 'technical difficulties' (that the German equipment manufacturer denied) and had reduced the flows over time to zero to put pressure on the Europeans through high winter gas prices and low supplies.

Your broader point is correct though, admitting to blowing it up would be bad press to any party.

Re: What the damaged Svalbard cable looked like

#247

Earlier quoted context omitted.

Can you use single mode fiber in a house, or do the transceiver only work over much longer distances? Is transceiver burn out an issue?

You can use SM for short runs, you just have to match the optics to the cable/distance you're looking to use. Tons of very fast single mode optics out there that only expect That said, it's likely not worth it, given that cabling is typically viewed as a ~10 year investment, and if you're installing OM4 Multimode fiber in a house you're not likely to hit the limit of that fiber within 10 years even in extreme use cas…

But why stop at 10 years? If the theoretical bandwidth limit of SM Fiber is above 100 Gbit/s then there is simply no way that a household will need more internal bandwidth than that. Even for the next 20-30 years, because other technologies (like SATA) will be the limiting factor.

I believe this could be a case of future proofing that will actually last 30-40 years, no?

Re: What the damaged Svalbard cable looked like

#248
post #236

Earlier quoted context omitted.

[flagged]

OK Mr super smart. Btw, you are the one missing the subtlety of “burning down your own good” vs “having it burned by a third party”. But sure, I'm the one who don't understand.

The underlying thing is it doesn’t necessarily matter in illustrating the point, especially in a discussion about moral hazard. This is because having insurance means the owner now has a strong incentive to see the place burn down (as long as it happens in a way that doesn’t stop a payout) because someone else will pay him if that happens. Assuming that payout is ‘worth it’ compared to the alternative of it not burning down.

It could be from leaving the door open ‘accidentally’ so someone ‘breaks in’ and does it (actually, or intentionally) or it could be hiring someone to do it - as long as they don’t get caught in a way that stops the payout. Or ignoring that pile of cardboard boxes near the oven, or the weird smoke smell near the electrical panel. Or not hiring security when they know they have angry protestors threatening to burn the place down. Or pissing off the local unstable homeless dude, and then not doing anything when he threatens to burn your place down. It doesn’t have to be a rational or conscious decision for it to be a problem for the insurer.

Moral hazard is a fundamental problem with insurance, because insurance by design and necessarily by definition removes loss/creates payouts for events that would otherwise leave the owner solely on the hook. Which if not done carefully, can alter behavior significantly.

It’s usually mitigable, or no one sane (or able to remain solvent long term!) will write such a policy. The early days of insurance, there were plenty of examples of people abusing it or weird edge cases causing insurance companies to go bankrupt. These types of Risks are so obvious though, and the industry so much more mature, that in modern history it’s usually due to corporate incompetence or the like.

For example, good luck getting a huge life insurance policy on a random homeless person and having it pay out if they die (regardless of if you had anything to do with their death).

Or not having a serious investigation if a friend gets in a car accident with you and gets lifelong disability injuries.

Insurance fraud is a crime created for the insurance industry to help protect them, and in theory reduces insurance costs and helps society.

Because this issue is always on their mind for a good reason.

They’re also a business in it to make a profit, and will happily exclude reasonable things and refuse to payout for reasonable claims if they think they can get away with it. Hell, I can’t think of any insurance company that likes paying out for anything.

But that doesn’t change the nature of moral hazard.

Your argument is weird because you’re essentially saying moral hazard isn’t an issue because there are laws making some of the more obvious damaging behaviors illegal.

But that’s like arguing it’s never dangerous to drive a car because there are laws making reckless driving, driving without a license, drunk driving, vehicular homicide, etc. illegal.

When actually, those laws are because at a fundamental level, it’s always dangerous to drive a car, these problems are common, and we’re attempting to mitigate them somewhat because we think (at a societal level) it’s worth it.

Re: What the damaged Svalbard cable looked like

#249

Earlier quoted context omitted.

The antismoking PSA that made the strongest impression on me, by far, was the one that showed a grandfather encouraging a baby to take a step. Eventually, the baby starts walking, and rushes over to the grandfather. And through the grandfather, who fades to translucency. It wasn't just me; that PSA made enough of a splash that it was called out on Friends . I've tried to find that PSA in the past, but with no success…

There have been some Oceanic anti-speeding ads that had the same effect on people, apparently. There's one where time freezes right before a collision and the person at fault apologizes for the little boy he's about to murder. There's one where the driver is talking to the ghost of his friend who died in a car crash. There's one where the grim reaper spins a roulette wheel every time a driver makes a mistake at an in…

> There's one where the grim reaper spins a roulette wheel every time a driver makes a mistake at an intersection.

In my imagination, this one would end with the roulette wheel stopping on 0, but the result of 0 not being depicted.

Re: What the damaged Svalbard cable looked like

#250
post #221
post #200

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That would require replacing all the satellites with new ones capable of doing that, which doesn't seem feasible. Starlink also doesn't have great coverage of the polar regions.

Starlink's laser system is already up and running. Back in January it was delivering over 42 petabytes per day: https://uk.pcmag.com/networking/150673/starlinks-laser-syste... “We're passing over terabits per second [of data] every day across 9,000 lasers,” SpaceX engineer Travis Brashears said today at SPIE Photonics West, an event in San Francisco focused on the latest advancements in optics and light. "We actually…

Again though, you can't do "Starlink from the satellites, so we don't rely on a specific ground station" unless all of the satellites support talking to Starlink, which they don't. That means they'd have to be replaced.
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