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Lasers enable satellite internet backbone, might remove need for deep-sea cables

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241–250 of 268 posts

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#241

Earlier quoted context omitted.

ETH Lausanne or Zürich?

I know about two newspapers who regularly say "ETH Lausanne", and I suspect these articles are written by similar pedants as some commenters here appear to be.

Internet points for you!

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#242

Earlier quoted context omitted.

ETH Lausanne or Zürich?

I know about two newspapers who regularly say "ETH Lausanne", and I suspect these articles are written by similar pedants as some commenters here appear to be.

It is just its German Name.

Also: https://en.m.wikipedia.org/wiki/ETH_Domain

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#243

Earlier quoted context omitted.

A proper cloud. Everybody understood what he meant, including you. Why the need for such extreme pedantry? Oh right. It's HN, home of uber-pedants.

No. I still don’t know what is meant by a proper cloud. I don’t have a starlink, but I’ve had plenty of other satellite systems in the past. None of these have had issues with clouds. Severe storms with heavy rain and lightning would affect it at times. With the older large dishes, heavy winds could cause it to move enough to degrade image. Clouds by themselves? No, not an issue. So, yet again I have to ask because a…

Not sure if you're being deliberately dense but he means a thick cloud. A very cloudy day where the clouds are very dense and voluminous.

If sounds like you don't agree with him, but don't pretend you don't understand him. Please.

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#244

Earlier quoted context omitted.

No. I still don’t know what is meant by a proper cloud. I don’t have a starlink, but I’ve had plenty of other satellite systems in the past. None of these have had issues with clouds. Severe storms with heavy rain and lightning would affect it at times. With the older large dishes, heavy winds could cause it to move enough to degrade image. Clouds by themselves? No, not an issue. So, yet again I have to ask because a…

Not sure if you're being deliberately dense but he means a thick cloud. A very cloudy day where the clouds are very dense and voluminous. If sounds like you don't agree with him, but don't pretend you don't understand him. Please.

You're going to need to show me charts with strength of signal being diminished by "proper" clouds before I'll even remotely come to thinking this isn't just FUD. So, no, I don't understand him, and yes, if this is the premise I do not agree with it.

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#245
post #183

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Suppose I a (hypothetical) very low frequency value based trader buy a million dollars worth of Apple. Apple should go up in price slightly, because someone (me) just made a big bet that it's going to do well. The market does this automatically. TSMC should also go up in price very slightly, because Apple doing well makes it more likely that TSMC (a major vendor of theirs) will also do well, and the market just learn…

But for you to buy a million dollars worth of Apple, someone sold a million dollars worth of Apple, right?

Sure, but assume for the hypothetical that the counter parties were a list of existing "I'll sell this much at this price" orders. I.e. they were existing information that the market already took into account.

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#246
post #236
post #232

Earlier quoted context omitted.

Well you're calculating bandwidth so yes

But Starlink would have no reason to exist in the first place if it didn't offer service in those remote places.

Most Starlink customers are in areas “easy” to serve by high speed internet like the eastern US. It’s really only economical because of poor internet access across most of the US compared to similar density areas in other developed counties.

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#247
post #198

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> Each submarine cable is 12+ strands which are DWDM multiplexed to 20-40 channels at 100-400gbps. Being able to pump 40 terabits per second up to a satellite from a single uplink, as they hope, is significant-- exceeding most subocean cables.

Preface: Day job is owning a low latency telco. a single cable system under construction(which we are buying part of) (there are over 30) has over 120t of capacity @400G waves, but we are already discussing doing 800G waves, which will double that. We currently operate on over 7 submarine cables, one of the landing stations we operate out of has over 10 cable landing which is over 850T of capacity across all cables.…

Most of us are not talking about Starlink. I'm talking about this optical uplink technology, which can push tens of terabits per second through the atmosphere between each uplink and satellite pair.

No, a single uplink can't replace a subsea cable.

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#248
post #238

Earlier quoted context omitted.

You are underestimating the capacity of modern core routers. A single PTX10016 router could route the entire starlink customer base with no over-subscription at all (230 Tbit/s vs 75 Tbit/s from 50 Mbit/s * 1.5M). Actual estimates of the total capacity of Starlink puts it more in the 20Tbit/s range (and that's without taking into account coverage over less populated areas).

First my 3 Tbit/s estimate was wildly pessimistic and only covered current network utilization. Adding missing countries plus ships more than doubles land area, 42,000 satellites is more than 10x current satellites, v2 is ~10x current individual satellite bandwidth. So current goals are at least 200x current bandwidth. (Satellites also so point to point links which we are ignoring in terms of what the total routing c…

I was only talking about the currently deployed constellation, which of course is much smaller, but for which we have actual numbers from measurements. For the completed Phase 3 constellation I have read numbers in the range from 1.7 - 2.3 Pbit/s as theoretical maximum. So would need around 8-12 PTX boxes to reach the same total routing capacity as the whole future constellation. The current single-fiber bandwidth record is 1.53 Pbit/s.

And nevermind that Starlink will run out of ground station / inter-satellite link capacity long before reaching the theoretical maximum.

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#249

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No. It's garbage, trading is supposed to serve human needs and should take place on human timescales. If I had a magic wand I'd randomly fuzz the timing of trades to remove a lot of incentives for HFT and some other kinds of automated trading, which are not much more than banging on a known deficiency in a slot machine. Proponents argue that HFT and other such innovations provide liquidity to markets; my skeptical ta…

If you want to buy an apple stock now at say 185$ (at time of writing). What gives you the confidence that you can buy it at this price? 1. You could put a limit order at 185$ or lower. But maybe no one is putting a sell order at this price? So you are stuck waiting for some time, maybe never if the price keeps going up? 2. You could put it at 190$ to trigger a trade but you risk buying 5$ more than what you original…

Yeah, that's the cost of doing business. If your business model depends on many many transactions with tiny margins, don't be a trader but become an exchange.

Re: Lasers enable satellite internet backbone, might remove need for deep-sea cables

#250
post #169

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Is liquidity even a real answer? The HFTs only work because the market would be made a moment later. A buyer and a seller already exist. If they didn't, it wouldn't be high-frequency trading. it would just be "trading". As far as I can tell, it neither benefits us, nor costs us. It siphons off a tiny fraction of money, too small to notice, but large enough in aggregate. Some parasite gets to survive, which is annoyin…

> The HFTs only work because the market would be made a moment later. A buyer and a seller already exist. Not at all. If you, for whatever reason, need to sell right now , putting in a market order in an illiquid market can cost you a lot. It can be discussed how big the contribution of HFTs to market making really is (large companies or exchanges often employ dedicated market makers, I believe?), but the benefit of…

Sure, liquidity is a good thing. But you only need enough liquidity to make your trade. Adding more provides zero benefit.

If the HFTs only trade when the market is already made (or will certainly be, milliseconds later) then they're not really adding any liquidity. They're just doubling the liquidity which was already sufficient.

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