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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

#171

Post by DylanDmitri »

soligern wrote: post #160
DylanDmitri wrote: post #150

Earlier quoted context omitted.

How about forcing public markets to bucket trades within say 2 second windows, executing best matches at the end of each period. Low friction and reduces value of millisecond latency advantages.

Then there would be algorithms that analyze the trades in those buckets, make a prediction on the outcome and carry out several counter trades to put into the same bucket. See a lot of people selling, cancel your buy order and replace with a short instead. Get a few of those bots involved and each bucket window would be exploding dueling pits of orders that would require insanely large systems to process.

These problems are fixable. Use blind bidding, and ban spoofing by preventing order cancellation within a bucket. Too many orders? Set a per-client limit.

Most of this is improvable with software. As other commenters point out, the resistance is from incumbent trading institutions who have a lot invested in the status quo.

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

#172

Post by notfish »

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…

Reddit seems to think that Starlink is already serving users via sat-to-sat optical links https://www.reddit.com/r/Starlink/comments/xsupcn/laser_link...

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

#173

Post by lxgr »

notfish wrote: post #172
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…

Reddit seems to think that Starlink is already serving users via sat-to-sat optical links https://www.reddit.com/r/Starlink/comments/xsupcn/laser_link...

Sure, high-bandwidth inter-satellite links are essential for providing service to remote regions (or even just to make ground station placement more economical), but the question here is whether they could ever economically compete with fiberoptics outright.

For extremely latency sensitive applications, I guess they will (e.g. for trading and real-time communications), but for everything else that can wait a few more milliseconds, I'd guess that the operational overhead and reduced reliability will never be worth it, especially if fiber already exists on the same path.

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

#174

Post by foobiekr »

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 even make the slightest dent in terrestrial networking. Starlink isn't even viable without most of the traffic doing two leg ground-satellite-ground for SP-network connected ground stations. 100% of that traffic is landing on the terrestrial internet.

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

#175

Post by soligern »

DylanDmitri wrote: post #171
soligern wrote: post #160

Earlier quoted context omitted.

Then there would be algorithms that analyze the trades in those buckets, make a prediction on the outcome and carry out several counter trades to put into the same bucket. See a lot of people selling, cancel your buy order and replace with a short instead. Get a few of those bots involved and each bucket window would be exploding dueling pits of orders that would require insanely large systems to process.

These problems are fixable. Use blind bidding, and ban spoofing by preventing order cancellation within a bucket. Too many orders? Set a per-client limit. Most of this is improvable with software. As other commenters point out, the resistance is from incumbent trading institutions who have a lot invested in the status quo.

Blinding bidding would not work given the current way NMS works and it wouldn’t be completely blind either ways, the exchanges would know and that’s a system ripe for abuse.

What is an order cancellation? Would different legs on a hedge count as a cancellation?

The closing window is a massive challenge as well. It would have to be accurate down to the nano second and you can bet the exchange is going to get litigated against depending on which bucket the order ends up in.

If you set up mandatory delays per client you would have each hedge funds split up into hundreds of shell companies to get around it.

Having worked at exchanges, most surveillance and analysis of trades happen after the close of day. You’re proposing a literal real-time surveillance system that would be absolutely massive in scale.

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

#177

Post by thadjones »

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…

In practice, considerable difficulty. Like you said LEO moves fast. You are talking 10 min in line of sight (LOS) depending on the orbit. So the handoff algorithms (and necessary network) are very challenging and cost prohibitive. I mention it in my earlier response but if you have a LEO network you need pretty substantial arrays to accommodate such a power load, and during “night” for whoever is using the network, you need transfer mechanisms to relay the data, using even more power during eclipse. This is a real challenge.

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

#178

Post by Retric »

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…

That Starlink estimate must be low, they currently have 1.5 million customers and a significant percentage of total bandwidth is over ocean and thus mostly wasted.

If you assume a pessimistic 100x over subscription and 50% waste over oceans and non serviced countries * 50mbps (upload + download) * 1.5 million customers that’s well over 1.5 TBPs current capacity for customers which then doubles when you include their base stations. And they that’s today when the current 3887 Satilites which mostly v1.0 and v1.5 which have dramatically less individual bandwidth than v2.0.

PS: Also your port estimate overstates total bandwidth as each point to point link requires a port on each side, and packets generally make multiple hops through the internet.

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

#179

Post by dmbche »

Unrelated - I'm reminded of the plans for beaming energy from orbital stations gathering sunlight, which instead uses microwaves.

I wonder how much these beams interact with the atmosphere? I can imagine lasers interact little, but wouldn't microwaves heat up water vapor on it's way?

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

#180

Post by Dylan16807 »

edgyquant wrote: post #116
ajsnigrutin wrote: post #87

Earlier quoted context omitted.

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.)

Then it probably wouldn't be hard to have increasing penalties for shorter durations, very especially sub-minute durations.
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