Lasers enable satellite internet backbone, might remove need for deep-sea cables • Hacker News Board

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

#251

Post by gnopgnip » Tue, Jun 27, 2023, 5:28 PM UTC

robertlagrant wrote: post #206

gnopgnip wrote: post #144

Earlier quoted context omitted.

Rent-seeking is an "economic activity to gain wealth without any reciprocal contribution of productivity". Or put another way it means societies resources are put towards wealth transfer instead of productivity/wealth creation.

Thank you; understood. I've just looked at the Wikipedia definition[0] as well, which is a little different, but I get the point you're making. I haven't thought about this enough, but one thing I'd note is that HFT is risk-taking, and taking a risk generally has the possibility of profit or loss. A second thing would be that the phrase "society's resources" is a bit dangerous, as it might let us think that the money…

>A second thing would be that the phrase "society's resources" is a bit dangerous, as it might let us think that the money they're using is somehow everyone's money. When in fact they're spending their money on this, hoping to make a profit.

From the perspective of the whole economy it is everyone's money. Rent seeking behavior is a dead weight loss due to market inefficiency. Through tax policy the incentives can change and largely remove this inefficiency.

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

#252

Post by Retric » Tue, Jun 27, 2023, 7:13 PM UTC

welterde wrote: post #248

Retric wrote: post #238

Earlier quoted context omitted.

First my 3 Tbit/s estimate was wildly pessimistic and only covered current network utilization. Adding missing countries plus ships more than doubles land area, 42,000 satellites is more than 10x current satellites, v2 is ~10x current individual satellite bandwidth. So current goals are at least 200x current bandwidth. (Satellites also so point to point links which we are ignoring in terms of what the total routing c…

I was only talking about the currently deployed constellation, which of course is much smaller, but for which we have actual numbers from measurements. For the completed Phase 3 constellation I have read numbers in the range from 1.7 - 2.3 Pbit/s as theoretical maximum. So would need around 8-12 PTX boxes to reach the same total routing capacity as the whole future constellation. The current single-fiber bandwidth re…

Ah, you said planned here so I assumed that was what you where talking about:

> The entire _planned_ starlink constellation has less aggregate switching capacity than a pair of current generation core routers.

I generally agree with those estimates based on how they’re defining limits though those definitions really depend on what you care about. Aka predicting actual utilization at one end vs just considering what the satellites could physically do in ideal conditions etc. Thus the theoretical impact of direct customer to customer links for a satellite over the Atlantic for example can vary wildly.

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

#253

Post by EMM_386 » Tue, Jun 27, 2023, 8:14 PM UTC

lxgr wrote: post #169

jfengel wrote: post #105

Earlier quoted context omitted.

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…

> 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.

Are high frequency traders trading in illiquid markets?

That would be surprising to me, it's not high frequency if it's not high volume, and you open yourself up to larger bid/ask spreads.

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

#254

Post by foobiekr » Tue, Jun 27, 2023, 8:45 PM UTC

Retric wrote: post #178

foobiekr wrote: post #174

Earlier quoted context omitted.

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…

Current generation 12 slot chassis with 51.2Tbps per slot is 612Tbps per chassis, and so a pair is 1228Tbps which is roughly your estimate. Companies like Juniper and Cisco sell tens of thousands of the previous generation per year _today_. Starlink is not even a drop in the bucket in terms of forwarding.

Moreover, with a very tiny exception over antarctica or open ocean, every single packet forwarded by starlink is hitting a terrestrial link after a single ground-space-ground hop.

Nobody is going to be making backbones out of Starlink or anything that looks like Starlink. Only the people who know nothing about modern networking performance think otherwise.

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

#255

Post by Retric » Tue, Jun 27, 2023, 11:47 PM UTC

foobiekr wrote: post #254

Retric wrote: post #178

Earlier quoted context omitted.

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…

Current generation 12 slot chassis with 51.2Tbps per slot is 612Tbps per chassis, and so a pair is 1228Tbps which is roughly your estimate. Companies like Juniper and Cisco sell tens of thousands of the previous generation per year _today_. Starlink is not even a drop in the bucket in terms of forwarding. Moreover, with a very tiny exception over antarctica or open ocean, every single packet forwarded by starlink is…

If you followed the thread, my estimate was ~3,000 TBps, welterde gave “1.7 - 2.3 Pbit/s” = 1700 to 2300 TBps. 1228 TBps is well below both of our estimates. Last I checked global IP traffic it’s still well under 2,000 TBps looking at the rate traffic is increasing Starlink really can act as a major internet backbone.

Also, Starlink customer to Starlink customer is very compelling for may applications. Undersea cables for example can create much higher latency between areas than their physical separation for example Australia to Madagascar. Similarly there’s still quite a bit of point to point microwave tower connections etc that can now be cheaply replaced.

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

#256

Post by foobiekr » Wed, Jun 28, 2023, 12:06 AM UTC

mlyle wrote: post #247

hyperionplays wrote: post #228

Earlier quoted context omitted.

Preface: Day job is owning a low latency telco. a single cable system under construction(which we are buying part of) (there are over 30) has over 120t of capacity @400G waves, but we are already discussing doing 800G waves, which will double that. We currently operate on over 7 submarine cables, one of the landing stations we operate out of has over 10 cable landing which is over 850T of capacity across all cables.…

Most of us are not talking about Starlink. I'm talking about this optical uplink technology, which can push tens of terabits per second through the atmosphere between each uplink and satellite pair. No, a single uplink can't replace a subsea cable.

Any free space optical approach you can imagine will be slower and noisier than the equivalent technology in a fiber. You are not going to get DWDM channel density in free space or throughput.

This is not real.

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

#257

Post by mlyle » Wed, Jun 28, 2023, 12:12 AM UTC

foobiekr wrote: post #256

mlyle wrote: post #247

Earlier quoted context omitted.

Most of us are not talking about Starlink. I'm talking about this optical uplink technology, which can push tens of terabits per second through the atmosphere between each uplink and satellite pair. No, a single uplink can't replace a subsea cable.

Any free space optical approach you can imagine will be slower and noisier than the equivalent technology in a fiber. You are not going to get DWDM channel density in free space or throughput. This is not real.

> Any free space optical approach you can imagine will be slower and noisier than the equivalent technology in a fiber.

Granted. More path loss, dispersion, potential for interference. The question is how well can you do?

> This is not real.

I believe ETHZ; of course there's more to do to make a practical system.

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

#258

Post by MagnumOpus » Wed, Jun 28, 2023, 7:25 AM UTC

soligern wrote: post #175

DylanDmitri wrote: post #171

Earlier quoted context omitted.

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…

It obviously works, given that many exchanges do have morning and evening auctions.

> The closing window is a massive challenge as well. It would have to be accurate down to the nano second.

It wouldn't have to be - one could even say first second is for bids, second second there are no bids but a delay to give auction results mid-second and allow people to process.

> the exchanges would know

They can be forbidden to sell that info real-time by their regulator (it arguably would be market abuse and that could be made explicit).

It is definitely not impossible like you are trying to imply. (Financial markets participant with 20 years in the market here, for what it's worth.)

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

#259

Post by welterde » Wed, Jun 28, 2023, 9:04 AM UTC

Retric wrote: post #255

foobiekr wrote: post #254

Earlier quoted context omitted.

Current generation 12 slot chassis with 51.2Tbps per slot is 612Tbps per chassis, and so a pair is 1228Tbps which is roughly your estimate. Companies like Juniper and Cisco sell tens of thousands of the previous generation per year _today_. Starlink is not even a drop in the bucket in terms of forwarding. Moreover, with a very tiny exception over antarctica or open ocean, every single packet forwarded by starlink is…

If you followed the thread, my estimate was ~3,000 TBps, welterde gave “1.7 - 2.3 Pbit/s” = 1700 to 2300 TBps. 1228 TBps is well below both of our estimates. Last I checked global IP traffic it’s still well under 2,000 TBps looking at the rate traffic is increasing Starlink really can act as a major internet backbone. Also, Starlink customer to Starlink customer is very compelling for may applications. Undersea cable…

You are not comparing the same thing here though. If you applied the same theoretical maximum method to all networking hardware (or even just core router class hardware) sold today you would arrive at numbers very very much in excess of a couple Pbit/s.

For it to be really viable as a backbone it would need to be able to do several 100 Gbit/s from one location and that Starlink cannot do (or is built to do). A single satellite has less than 100Gbit/s of RF capacity and you will only have a couple visible above you at any one time. And after that bottleneck comes the inter-satellite link capacity bottleneck which is less than half of that if the information I have found is correct (4 links à 10Gbit/s). I don't think they will be able to sell more than 10 GBit/s service to anyone and that only in not so populated areas.

A single datacenter can reach low Tbit/s of connectivity _alone_ _today_. I don't see how it could make any dent whatsoever in the backbone market.

The other usecases are a different discussion and not as dependent on very high bandwidth numbers.

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

#260

Post by Retric » Wed, Jun 28, 2023, 12:44 PM UTC

welterde wrote: post #259

Retric wrote: post #255

Earlier quoted context omitted.

If you followed the thread, my estimate was ~3,000 TBps, welterde gave “1.7 - 2.3 Pbit/s” = 1700 to 2300 TBps. 1228 TBps is well below both of our estimates. Last I checked global IP traffic it’s still well under 2,000 TBps looking at the rate traffic is increasing Starlink really can act as a major internet backbone. Also, Starlink customer to Starlink customer is very compelling for may applications. Undersea cable…

You are not comparing the same thing here though. If you applied the same theoretical maximum method to all networking hardware (or even just core router class hardware) sold today you would arrive at numbers very very much in excess of a couple Pbit/s. For it to be really viable as a backbone it would need to be able to do several 100 Gbit/s from one location and that Starlink cannot do (or is built to do). A single…

Core routing hardware isn’t sold at multiple Pbit/s because no location on earth has that much traffic. Nobody is wasting that kind of money buying hardware when they don’t have fiber to make use of it. Starlink is aiming physically to eventually have 10+ Pbit/s worth of actual hardware because customers aren’t spread evenly across the globe so there’s inefficiencies involved. The only unfairness is comparing future equipment to current equipment.

First data centers very wildly in size and have connections to multiple networks for redundancy, Starlink would be very appealing from that standpoint. Also you’re underestimating bandwidth here, V2 mini are ~80Gbps full V2 weigh 2.5x as much and presumably the bandwidth difference is even higher, but they aren’t launching hardware yet so it’s unclear. Any given location several satellites above it at the current density, at 42,000 you’re talking 50+. Plus if it’s data center to Starlink customer then you’re effectively replacing a Starlink ground station so they might make such installations very cheap.