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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

#111

Post by [deleted] »

cortesoft wrote: post #103
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…

In a healthy market, HFTs serve as market makers, and allow normal traders to have faith that prices will be consistent at all exchanges. If there is enough competition, an HFT will have very low profit.

[deleted]

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

#112

Post by dylan604 »

NohatCoder wrote: post #73
eqvinox wrote: post #65

This sure sounds useful, but "might remove need for deep-sea cables" is quite silly. Anything they do to cram bandwidth into their laser link can reasonably also be applied to fiber optical cables. Except the fiber optical cables come in bundles of 12 to 144 with absolutely no separation issues. Replicating that over open space (air or vacuum), if reasonably possible at all, will chug significant amounts of power in…

On top of this I really doubt the claim about working in bad weather. Some weather will work, sure, maybe at reduced speeds. But if there is a proper cloud in the way, the near-visible 1550 nm light will be scattered completely.

what is a proper cloud? it does not seem to be a term frequently used when discussing clouds: https://en.wikipedia.org/wiki/Cloud

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

#113

Post by cycomanic »

gorkish wrote: post #21
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…

> 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.

Photonic bandgap fibres are not used in submarine cables their loses are too high. There are recent antiresonant fibres (NANF) which can achieve lower losses than even SMF. However production capabilities are not ready yet to make the amount of fibre necessary for submarine. The startup (out of Southampton) that pioneered these was recently acquired by Microsoft.

We probably see these fibres for links between the exchange and data centres first (although there it is difficult to beat RF links, as they are direct line of sight)

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

#114

Post by [deleted] »

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…

[deleted]

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

#115

Post by ortusdux »

thesz wrote: post #99
ortusdux wrote: post #59

Earlier quoted context omitted.

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 r…

From [1]:

"Space lasers allow Starlink satellites to connect directly to one another, eliminating the need for a local ground station and enabling Starlink. to deliver service to some of the most remote locations in the world - like Antarctica."

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

#116

Post by edgyquant »

ajsnigrutin wrote: post #87
willis936 wrote: post #80

Earlier quoted context omitted.

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…

If you buy a stock, you must keep (hold) it for eg. 30 days (or 7, or 60, or whatever). Compute all you want, whenever you want, but instead of millisecond timings, optimize stuff for at least some time. Maybe even a tax on stock profits, which is really high and falls after some time of ownership of such stock (we have this in slovenia, but it's not really high in the first place, and time brackets go less than 5 ye…

There already is a penalty for not holding and a tax on wash trading (selling and rebuying within 30 days.)

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

#117

Post by bjelkeman-again »

elif wrote: post #104
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…

HFT isn't even that harmful. What's harmful is brokerages that hold large portions of financial instruments who take advantage of customers' live buying and selling with delayed swaps, intentional front running, etc. This is how the stock market was bullied before HFT, options markets, trading bots, etc enabled 'everyone' to do skeezy arbitrage and not just market makers. The only meaningful way to limit the efficacy…

Wouldn’t a financial transaction tax be the friction required? https://en.wikipedia.org/wiki/Financial_transaction_tax

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

#118

Post by patmorgan23 »

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…

Small cost per trade (tax/fee)

Minimum time between buying and selling the same ticker

Mandatory network 'speed bump' of a few ms between the exchange and any trading parties

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

#119

Post by patmorgan23 »

ajsnigrutin wrote: post #87
willis936 wrote: post #80

Earlier quoted context omitted.

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…

If you buy a stock, you must keep (hold) it for eg. 30 days (or 7, or 60, or whatever). Compute all you want, whenever you want, but instead of millisecond timings, optimize stuff for at least some time. Maybe even a tax on stock profits, which is really high and falls after some time of ownership of such stock (we have this in slovenia, but it's not really high in the first place, and time brackets go less than 5 ye…

Even if you said you have to hold it for 3 hours that would cut against the worst of the HFTs

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

#120

Post by cycomanic »

I like the ETH result and it is an impressive feat (I know some people involved in that work). That said the article is a lot of rubbish. First there is the weird focus on lasers, all (relevant) Optical Communication uses lasers, including fibre comms. Then they make it sound like this is to replace fibre, again rubbish.

The amount of data going through fibres is absolutely staggering, replacing this with intersatellite links is just not going to happen. First you still need fibre to connect your ground stations (and you need quite a bit of redundancy due to weather) and there are still a lot of unsolved problems (tracking and pointing for example). However there are many interesting applications of optical satellite links and quite a few players are investing in it, the big one is actually data connections for scientific space missions.

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