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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

#191

Post by quickthrowman »

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.

Liquidity, lower volatility, and lower transaction costs, for starters.

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

#192

Post by lend000 »

quickthrowman wrote: post #189
lend000 wrote: post #129

Earlier quoted context omitted.

That's the price you pay for liquidity, and the alternative (paying a difference in price far more than 0.01%) makes everyone worse off except other people competing in the markets. The money HFT's make comes from other people trading the zero sum short term trading game, not you (assuming you are longer term investor or non-participant in the market), so why should you or others in your situation get worked up about…

It’s weird to be how much some people hate market makers and traders who apply arbitrage strategies. I don’t think there would be as much hatred for HFTs if people understood what it is they do. They make markets on securities and arbitrage things. For example, creating units of SPY when it gets too far above NAV to bring the NAV back in line with the index. I’m sure there are more strategies I’m unaware of, but it’s…

I agree; it's as abstract as software but you can't really go to school to learn about it. It's more of an indictment of the tribal nature of humans and today's popular political narratives than of the intelligence of the OP's, who I assume are very smart. Deep-rooted emotions like jealousy and fear of the unknown can lead to shallow dismissals of complex and important systems.

It would be slightly amusing to see some sort of HFT ban, only to see people speedrun re-inventing HFT as numerous problems unfold, like dad putting in a market order for AAPL on a day it had a VWAP of $185 and having his trade execute at an average price of $690. Or more serious problems like shortages and surpluses of commodities in different locations due to bad price information.

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

#194

Post by vgatherps »

Terr_ wrote: post #133
vgatherps wrote: post #126

Earlier quoted context omitted.

If everybody is exactly 350us slower, then it’s still the same game. Iex also offers a variety of (dark) order types that can pull back without the 350us delay if iex believes the incoming flow will be toxic

> If everybody is exactly 350us slower, then it’s still the same game. IANATrader, but I don't think that's entirely true. Yes, it won't stop Carol from getting information from somewhere and then running in front of Alice to the same exchange. [0] However even fixed-delays [1] can still create uncertainty about what price your order may actually execute at when it hits the server, which is something HFTs rely on mor…

> However even fixed-delays [1] can still create uncertainty about what price your order may actually execute at when it hits the server, which is something HFTs rely on more heavily than other traders, since their strategy depends on high-certainty that they will have a small positive margin on every trade

This is also true on every single other exchange, albeit to a smaller degree. You have a larger queue of possible things that may have happened, but this issue exists everywhere. No exchange has instant entry.

On a very short timescale things are very jumpy - nothing happens for a while, and then everything happens all at once. The queuing problem tends to be more of “did another hft beat me to the same event”, not general random other events, so queues like IEXs tend to be emptyish anyways.

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

#195

Post by asadotzler »

thecosas wrote: post #58
oceanplexian wrote: post #34

Earlier quoted context omitted.

It also circumvents the biggest problem with fiber, politics. Starlink doesn’t need permission to run a backbone across (or rather over) a country. This will be revolutionary for people in Africa, South America, and huge swaths of Asia/Australia where a few telecom monopolies have artificially jacked the price of transit.

It definitely helps mitigate the infrastructure buildout hurdles (which are not small), but they would still need to jump through any "I need to do business in this country" regulations, etc.

Only if they want to bring a signal down to the ground. Unlike fiber, LEO sats can send data across an entire continent of countries or states without getting permission from any of them. Wanna connect Toronto to Mexico City with fiber, gotta get the US and half a dozen states and dozens of counties all to give you easement. Not so with space lasers :-)

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

#196

Post by asadotzler »

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?

Here where I've been on 1.5 Mbps for 15 years and there is literally no other alternative. No cell coverage. No cable. Mountain blocks GEOsat. Copper is a 6 mile run to nearest town so DSL is out too. Also, I'm literally 12 miles from the Googleplex. Yeah, broadband is a mess outside of cities and suburbs.

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

#197

Post by asadotzler »

thadjones wrote: post #164

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 wast…

ISLs are active today, providing low-latency broadband to thousands, perhaps tens of thousands of Starlink's 1.7-ish million customers where there are no nearby ground stations. I'm not sure if that's "mainstream" but when major cruise lines and Alaskans are happy active customers, it feels like it's getting mainstream to me.

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

#198

Post by mlyle »

foobiekr wrote: post #174
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 article is 100% rubbish. Just complete trash. Each submarine cable is 12+ strands which are DWDM multiplexed to 20-40 channels at 100-400gbps. The entire _planned_ starlink constellation has less aggregate switching capacity than a pair of current generation core routers. The market for terrestrial ethernet _routed_ 400Gbps ports is 10k+ annually and 800Gbps is just getting warmed up. Satellite is not going to ev…

> 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.

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

#199

Post by dermesser »

eqvinox wrote: post #153
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…

(really off-topic) The Z on ETHZ is important, ETH on its own is just (loosely) "university", the Z makes it the Zürich one ;D. There is exactly one other: EPFL in Lausanne. (And you can technically call them EPFZ and ETHL if you really want to confuse people.) (EPF [École Polytechnique Fédérale] is just the French version of German ETH [Eidgenössische Technische Hochschule]. Funnily enough both have pretty good inte…

...yet, when saying "ETH" everyone knows what is being referred to. Except for crypto bros.

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

#200

Post by chrismorgan »

gpm wrote: post #183
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…

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?
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