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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

#161

Post by mxkopy »

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…

HFT is one of the only ways you can make money directly by making computers go faster. Gaming and edge computing are the other ways.

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

#162

Post by killjoywashere »

Whenever I hear of exotic comms stuff like this, I think about command and control use cases. Quantum computing is about security of the cryptographic security infrastructure (PKI, TLS, etc). New physical layers are all about diversification. It's less about disruption and more about security.

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

#163

Post by lxgr »

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…

> HFT changes these "beliefs in company" to "beliefs that the stock will go up", and the timeframe of those "beliefs" is sometimes in milliseconds.

None of this prevents you from investing using whatever long-term paradigm you prefer. The effects of HFT on that investment style are negligible.

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

#164

Post by thadjones »

Lasercom has been demonstrated well on Earth but it still is a very nascent technology in the space domain. There are several challenges that lasercom faces.

First, in order to enable global communication you need a constellation and good constellation management. This requires fewer spacecraft if you are in GEO, but GEO spacecraft tend to be larger and more expensive.

Second, lasers draw a lot of power. Most is waste heat as far as the spacecraft is concerned, but this can become a problem if the duty cycle is high. High power means much larger arrays, and for a LEO constellation, serious eclipse challenges.

Finally and most importantly, pointing is a challenge. Maintaining pointing control in space is hard, and lasers require much greater accuracy as compared to RF. With RF, the lobes are relatively large and allow some play when it comes to downlink to ground. Lasers are unforgiving.

I’ve led several spacecraft missions with lasercom terminals, and every time it has made development markedly more challenging. I think it will be quite a while before it is mainstream, and certainly before it replaces fiber.

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

#165

Post by voxelghost »

cycomanic wrote: post #120

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 intersatell…

The focus of the article seems to reflect the focus of the work it is describing quite well?

https://www.nature.com/articles/s41377-023-01201-7

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

#166

Post by lxgr »

tails4e wrote: post #106
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…

I agree. HFT goes against the original ethos of a market open to all. Instead of trading on the merit of a given company, it simply reinforces the market is increasingly gamified and unfair. It's like futures, no ones cares about the commodity being traded, or that doing so can really hurt people and business that rely on that item, it's just another item to be gambled.

> Instead of trading on the merit of a given company, it simply reinforces the market

What you're proposing is actually not a ban on HFT, it's a ban on investment strategies other than value investing. How would you implement that in practice? Have every investor swear under oath that they do believe in the company's inherent value, regardless of the rest of the market's behavior?

> HFT goes against the original ethos of a market open to all.

What "original ethos" is that? And even if it existed, wouldn't excluding certain investors go against it much more?

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

#167

Post by WatchDog »

killjoywashere wrote: post #162

Whenever I hear of exotic comms stuff like this, I think about command and control use cases. Quantum computing is about security of the cryptographic security infrastructure (PKI, TLS, etc). New physical layers are all about diversification. It's less about disruption and more about security.

Interesting, fibre optic cables can be tapped by an adversary, it's difficult to physically secure the entire length of the cable.

Satellite radio communications can be monitored, as the signal is cast over a wide area.

Satellite laser communications however, would be much more difficult to tap into.

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

#168

Post by lxgr »

criddell wrote: post #97
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…

> 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.

> I think that's only true for IPO shares

Not quite: By buying shares in a company, you positively influence its share price, which reduces cost of capital for the company (in case it needs it).

Arguably, the difference in impact (in terms of enabling/steering companies to do things) between the IPO and secondary market these days is probably negligible compared to any two single private funding rounds.

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

#169

Post by lxgr »

jfengel wrote: post #105
EMM_386 wrote: post #96

Earlier quoted context omitted.

The common answer will be "liquidity". The honest answer is probably nothing.

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 market making itself should hopefully be obvious.

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

#170

Post by lxgr »

Loughla wrote: post #82
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…

Honestly, I don't understand how they're legal, either. HFT just seems like the most naked of naked cash grabs in finance.

This seems to be a common sentiment – but do you know what HFTs actually do, and why it works?

I was pretty skeptical too, but the more I look into it, the more it just boils down to market making (providing liquidity) and arbitrage (improving price quality across exchanges).

There might be dirty tricks there too – I'm only speaking for legal trading practices here. And if an HFT makes its profit using illegal methods, what's the difference between that and other financial crimes like insider trading, collusion to frontrunning etc.?

I don't really get the (to me somewhat irrational/uninformed) focus on HFTs, when things like payment for order flow probably "siphons off" just as much from retail investors' trades.

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