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

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

#91

Post by modeless »

cma wrote: post #75
ortusdux wrote: post #59

Earlier quoted context omitted.

Starlink's laser connections have been active for a year now.

What's the latency NY to Australia all over Starlink with laser interconnect now?

I don't know if Starlink is routing packets that way. I think it's more likely that they route packets to a ground station as soon as possible to save laser link capacity for customers that actually need it, like ones in the middle of the ocean. If you want your packets routed all the way around the Earth through space then you'd probably need a special contract with SpaceX.

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

#92

Post by ortusdux »

willis936 wrote: post #80
ajsnigrutin wrote: post #76

Earlier quoted context omitted.

Am I the only one who thinks HFT should be forbidden? Stocks and investments are a nice thing to have, since you can buy a share of a company you believe in, they get the money, do stuff, you get dividends and in the end can sell the stock after some time too. HFT changes these "beliefs in company" to "beliefs that the stock will go up", and the timeframe of those "beliefs" is sometimes in milliseconds. This turns cl…

What would that look like? If you rate limit stock exchanges to something like 1 update per minute then there will likely be the same amount of networking and computation going on to speculate on the next update and calculate optimal plays. It just moves it to behind closed doors where it is harder to know if shenanigans are going on. It would take a heavier hand to push against this problem. I'm all for it, I'm just…

A few congress people put forth a bill that would add a 0.1% tax on trades. This would be a rounding error for most traders, but a significant value for HFT.

https://www.brookings.edu/opinions/congress-wants-to-tax-sto...

I wonder what happened to it.

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

#93

Post by aj7 »

I suspect the tracking and switching infrastructure, the sophistication of free space lasers with their adaptive optics, and the inclusion of satellite receiver-transmitters with their own adaptive optics will not be competitive with laying a passive undersea cable for at least a decade.

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

#94

Post by lm28469 »

nottorp wrote: post #33
NelsonMinar wrote: post #25

The key thing here is it allows for very high bandwidth to go almost anywhere on earth, not just spots where it's easy to land a cable. Starlink's already demonstrated how great that is for consumer bandwidth (50Mbps); a multi-gigabit link terminated at a satellite is fantastic. The part that impresses me most is they're talking about LEO satellites. Those move fast! Starlink does this with a very impressive phased a…

> how great that is for consumer bandwidth (50Mbps) 50 Mbps is great consumer bandwidth where?

I'm on 50mbps and 99% of the time it's too fast for my needs. I've lived on 10mbps capped 4g for a month and I didn't notice any problems either

Anything that allows video communication/streaming is "great" imho, it certainly is more than enough for most people.

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

#95

Post by colinsane »

samtho wrote: post #57

This tech is really cool, but as they mentioned, they have not tested this with a moving satellite. Because any antenna would need to be localized on a satellite for transmission, you’re going to be stuck with having to maintain (likely) expensive and precise motors who’s job it will be to run in perpetuity. However, I would be confident that stepper motors of this grade will come down in price or will become more av…

> Because any antenna would need to be localized on a satellite for transmission, you’re going to be stuck with having to maintain (likely) expensive and precise motors who’s job it will be to run in perpetuity. However, I would be confident that stepper motors of this grade will come down in price or will become more available.

the article says they direct the laser using a MEMS device. not dissimilar to the micromirror arrays used in DLPs for decades, i would assume. you’ve definitely got options that don’t require stepper motors or any macroscopic moving parts here.

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

#96

Post by EMM_386 »

ajsnigrutin wrote: post #88
542458 wrote: post #86

Earlier quoted context omitted.

> since you can buy a share of a company you believe in I don't think this is generally true. Stock trading isn't charity, it's done to make a profit. Almost trading is done on the basis of second order effects, and has been for as long as there's been a stock market. Stocks aren't given value by the company being profitable, they're given value by what other people are willing to pay for them (okay, yes, dividends a…

Well sure it's for profit, but what exactly do we (the society) get if we allow millisecond investments in our companies? Compared to classic, long-term investments.

The common answer will be "liquidity".

The honest answer is probably nothing.

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

#97

Post by criddell »

ajsnigrutin wrote: post #76
ortusdux wrote: post #13

Current fiber optic cables transmit signals at 2/3rds the speed of light. Modeling has shown that starlink's laser backbone would allow it to beat deep-sea cables in some situations. This article estimates a NYSE -> FTSE reduction from 76ms to 43ms. I wouldn't be surprised to learn that there is a HFT bidding war going on. https://archmeregreenarch.org/1456/news/starlink-and-the-ris... There is a newer version of fib…

Am I the only one who thinks HFT should be forbidden? Stocks and investments are a nice thing to have, since you can buy a share of a company you believe in, they get the money, do stuff, you get dividends and in the end can sell the stock after some time too. HFT changes these "beliefs in company" to "beliefs that the stock will go up", and the timeframe of those "beliefs" is sometimes in milliseconds. This turns cl…

> you can buy a share of a company you believe in, they get the money, do stuff

I think that's only true for IPO shares which often aren't available to retail investors/gamblers like me.

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

#98

Post by gnopgnip »

willis936 wrote: post #80
ajsnigrutin wrote: post #76

Earlier quoted context omitted.

Am I the only one who thinks HFT should be forbidden? Stocks and investments are a nice thing to have, since you can buy a share of a company you believe in, they get the money, do stuff, you get dividends and in the end can sell the stock after some time too. HFT changes these "beliefs in company" to "beliefs that the stock will go up", and the timeframe of those "beliefs" is sometimes in milliseconds. This turns cl…

What would that look like? If you rate limit stock exchanges to something like 1 update per minute then there will likely be the same amount of networking and computation going on to speculate on the next update and calculate optimal plays. It just moves it to behind closed doors where it is harder to know if shenanigans are going on. It would take a heavier hand to push against this problem. I'm all for it, I'm just…

Raising the financial transaction tax to 0.1%, 1$ per $1000 would eliminate the vast majority of unproductive and rent seeking HFT without negatively effecting liquidity. The US already has an FTT to fund the SEC, implementation should be straightforward. Currently the rate is very low, about 0.002%. Raising the rate would be minimally impactful for longer term investors and generate on the order of $50b a year for the government.

Hong Kong has an FTT of 0.13% currently, it was 0.1% from 1993-2021 so you can compare HFT impacts on these markets. Or compare dozens of other countries with similar rates, Switzerland, Taiwan, France, Italy, Japan.

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

#99

Post by thesz »

ortusdux wrote: post #59
gorkish wrote: post #21

Earlier quoted context omitted.

> require a generational shift to deploy. Photonic bandgap / Bragg fiber is being produced in quantity, and some subsea cables are using it. I'm pretty sure it's the satellite lasers that require the generational shift. One subsea cable has no bearing on any other; once the first is installed, you're up and running. not so with laser-connected swarms.

Starlink's laser connections have been active for a year now.

[1] https://wccftech.com/starlink-turns-on-laser-satellites-for-...

Judging from [1], lasers are used not for inter-satellite links, but for downstream or upstream links - from satellites to the ground.

Intersatellite links require precise machinery, such as picometer-precise positioning systems [2].

[2] https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/prod...

Also, there should be compensation for satellite rotation, initial targeting and tracking. At ~12km between satellites (~4000 on 550 km orbit), the (possible) target of laser signal receiver which, say, is one meter in diameter will be one third of an angular minute. It is not impossible to target that initially, but keep in mind that laser beam is very focused and its power drops significantly with the angular distance.

I really do not know how to even target satellites' receivers initially, let alone compensate for rotation and track these targets afterwards.

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

#100

Post by ajmurmann »

ajsnigrutin wrote: post #76
ortusdux wrote: post #13

Current fiber optic cables transmit signals at 2/3rds the speed of light. Modeling has shown that starlink's laser backbone would allow it to beat deep-sea cables in some situations. This article estimates a NYSE -> FTSE reduction from 76ms to 43ms. I wouldn't be surprised to learn that there is a HFT bidding war going on. https://archmeregreenarch.org/1456/news/starlink-and-the-ris... There is a newer version of fib…

Am I the only one who thinks HFT should be forbidden? Stocks and investments are a nice thing to have, since you can buy a share of a company you believe in, they get the money, do stuff, you get dividends and in the end can sell the stock after some time too. HFT changes these "beliefs in company" to "beliefs that the stock will go up", and the timeframe of those "beliefs" is sometimes in milliseconds. This turns cl…

Eric Ries with his Long Term Stock Exchange for me really nailed this issue. HFT is the epitome of all the reasons why the LTSE is great.
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