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I don't understand the math. 800 satellites at 23 gbps seems to be able to provide 1 gbps to 18,400 connections at any given time. This seems to be many magnitu
by whiddershins 10y ago
I don't understand the math. 800 satellites at 23 gbps seems to be able to provide 1 gbps to 18,400 connections at any given time. This seems to be many magnitudes off from what would be needed to have any impact. What am I missing?
- bumblebeard 10y ago"Once fully optimized through the Final Deployment, the system will be able to provide high bandwidth (up to 1Gbps per user), low-latency broadband services for consumers and businesses in the US and globally,” SpaceX told the FCC. “Subject to additional development work, SpaceX plans to design and manufacture its own satellites, gateway earth stations, and user terminals.” Home Internet customers would receive a "low-profile user terminal that is easy to mount and operate on walls or roofs." I guess the numbers depend on what "final deployment" means. Presumably more satellites with higher bandwidth.
- deleted 10y ago[deleted]
- nabla9 10y agoSpaceX plans worldwide satellite Internet with low latency, gigabit speed and very high price.
- bumblebeard 10y agoI was wondering about the price too. If the bandwidth is actually going to be as limited as the numbers in this article imply then it'll probably be out of reach for most of the people who need it.
- icanhackit 10y ago> [...] and very high price Even if that's true they've effectively subsidized their rocket business and gained more experience through a greater number of launches. Often Elon is trying to kill more than one bird with every stone he throws - maybe he knows he'll need a solar network to support a Mars colony. This is how he gains the tools, people and experience to eventually roll it out.
- aerovistae 10y agoDoubt it. Elon's made his fortune by replacing existing products with superior alternatives. He's said in every case that driving cost down is one of the most important parts of creating something people want. Why do you think he wouldn't do the same here? He knows everyone hates existing telecoms. He's trying to create a better alternative.
- quonn 10y ago> He knows everyone hates existing telecoms. Not true everywhere. I'm paying < $40/month for a 100 MBit connection and I don't hate my telecom.
- ctchocula 10y agoCompetition makes a big difference. Just over a year ago with Google Fiber rearing up, my ISP offered 150Mbps for $35. This year with Google Fiber downsizing, the big American ISPs are back to their duopoly: 25Mbps for $40 or 10Mbps for $30. Hopefully SpaceX is able to force them to lower rates for everyone.
- legolas2412 10y agoIt's not going to replace internet for cities/towns. Think of the latency! It is directed towards middle of nowhere areas where nobody provides fiber.
- nitrogen 10y agoIf the satellites are in LEO, latency won't be that bad. At 700km height mentioned elsewhere in the thread, added latency might be 10-20ms based on halving the numbers at https://www.dslreports.com/forum/r100277-Whats-the-latency-predicted-with-LEO-satellites https://www.dslreports.com/forum/r100277-Whats-the-latency-p... (from 16 years ago).
- rconti 10y ago30ms of latency is mentioned in the article, due to the low orbital altitude.
- joshualross 10y agoThe full constellation would be 4,425 satellites.
- digler999 10y ago1gbps may mean the theoretical max physical-layer link from a terrestrial client to one or perhaps multiple, satellites, assuming 100% signal strength, no other users, etc. More than likely it would be 1gbps asymmetric from the bird and a much lower upload speed, just like DSL.
- gibybo 10y agoPeople aren't generally using a 1 gbps connection at 100% capacity 100% of the time. If we assume customers use an average of 1 TB of data per month and the time they use it is pretty spread out (seems reasonable since they are going to be spread out accross timezones eventually), you can serve about 6 million customers with 800 satelites @ 23 GBPS, and with 4400 @ 23 GBPS you could do ~33 million. Admittedly these numbers are all best case scenarios (except maybe the 1 TB average, that's probably generous), but even if you divide by 2 it's a decent number of people.
- andrepd 10y agoStill. What's the cost of deploying 800 sattelites vs cost of fiber infrastructure for 6 million people?
- piptastic 10y agoIt depends on how far apart those 6 million people are and how much infrastructure is already in place.
- spynxic 10y agoSince satellites handle most worst-case distance scenarios with respect to fiber, it is reasonable to assume a connection spanning the world (including access to remote areas)
- soperj 10y agoSo long as it breaks even, SpaceX comes out ahead, since they're deploying the sats, and learning how to build the sats in a mass produced way.
- randall 10y ago+ economies of launch scale.
- Tuna-Fish 10y ago
- lanna 10y agonobody uses their connection at full capacity 100% of the time
- mey 10y agoThat sounds like a challenge
- brianwawok 10y agoWell people that leave torrents on 24/7 can.
- sly010 10y agoBut a lot of people use it at near full capacity on Sunday evenings when a new episode of Westworld is out.
- samfisher83 10y agoWhat if everyone starts streaming 4k?
- NeutronBoy 10y agoThe same way terrestrial data links work - you work out your usage patterns and make compromises. You can't guarantee 100% bandwidth available 100% of the time. This is some of the rationale behind data caps. While you can still exceed the available bandwidth if all your customers get on and use their connection to the max, a data cap forces your customers to meter their usage out over the month and reduce the impact of this concurrent usage pattern.
- Nokinside 10y agoIt will be expensive bandwidth no matter what. The way they can make this work is if they 1) are targeting traditional satellite internet customers (ships on the sea, commercial aviation, etc) and 2) integration with 5th generation mobile networks trough wireless network virtualization. Mobile network provider can sell a service where traveling customer pays extra for connection that works in the middle of nowhere. When the device is within normal cell network or WiFi, connection goes trough those networks, when they are sailing with their yacht, it can jump from the picocell in the boat or backpack to the satellite network. At any given time there may be millions of customers who pay little extra for coverage and just few tens of thousands who actually use it.
- bigiain 10y ago"commercial aircraft carriers" That made me stop and think for a bit...
- AceJohnny2 10y agoYou mean like the Raft? https://en.wikipedia.org/wiki/Snow_Crash https://en.wikipedia.org/wiki/Snow_Crash
- bigiain 10y agoExactly where my head started going... Then "No hang on. The rest of this comment isn't making sense now, back up bak up backup. Oh... _that's_ less interesting." :-) (Gah - and don't you hate it when people stealth-edit their comments and make you look insane? For the record, the parent originally said "commercial aircraft carriers" instead of "commercial aviation". I may be insane, but there's a completely plausible explanation for this comment thread and it can't be used as evidence of my lack of sanity, ok?)
- Tuna-Fish 10y agoThe frequencies they intend to use limit them to antennas roughly the size of a pizza box, which is a little bit too unwieldy for a backpack...
- Veratyr 10y agoTo take home users as an example, the residents generally sleep 8-10 hours a day, work 9 hours a day, commute ~1 hour a day, leaving only about 6 hours of free time at home a day. Assuming they spend that entire time watching 4K Netflix (25Mbit), they'll have used ~2TB in a month, or ~6Mbit/s total. Averaging bandwidth out over the whole month, each satellite would be able to support 3800 people. With the 4400 satellites they intend to deploy, they could support 16 million people. Of course you generally need to provision for peak bandwidth rather than average so these numbers aren't even close to accurate but I think it's a rough explanation for why you don't need to fully provision every link.
- tim333 10y ago2TB/month is a lot. Home data caps tend to be more 10 - 40GB and I've got 4GB data on my phone which is fine for most stuff except video. I doubt the service will be very cheap - sat services are usually more than cellphone data.
- cortesoft 10y agoYeah, most people sleep at the same time. Working for a CDN, we see our POPs gets about 4x traffic at peak compared to low times.
- freehunter 10y agoMost people sleep at the same time in one given geography, but if you're looking at the world, those times are pretty well distributed. Assuming I'm sleeping 8 hours a day, even the continental US only has 5 hours per day when everyone is asleep when you account for time zones. But APAC, ME/Africa, and Europe are all pretty reliably awake at that time.
- cortesoft 10y agoYeah, but that doesn't mean you can just put all the satellites right above the part of the world that is awake - so you are still going to not have a perfectly efficient system.
- elihu 10y agoLots of people have mentioned over-subscription, but another consideration is that while 1gbps connection speeds may be offered, they're likely to have other speeds as well at different costs. For a lot of people, even 100kbps would be an improvement over what they have (which might be dial-up, might be satellite with 2-second ping times, or might be nothing). I myself probably wouldn't notice much difference between 5mbps and 1gbps, as long as youtube works. This could be a big deal for the huge under-served population in rural America and in developing countries. Incumbent telcos would have to have service at least as good/cheap as SpaceX's internet service to stay in business. I hope they introduce a low-cost, relatively low bandwidth plan that's accessible to the world's poor.
- legolas2412 10y agoIt might be good for people living in remote places in USA. But the world's poor have internet connectivity, 3G/LTE is cheap and widely available. Don't go by US prices for data. Cellular plans here in India are cheap.
- sly010 10y agoSatellite communication at the moment is very expensive (like dollars per kilobyte expensive) not because of the limitations of long distance wireless communication in general, but because most of our satellite equipment up there is old and outdated. At some point as we developed world wide communications, laying down long distance fiber became cheaper than deploying communication satellites, and the existing satellites had enough capacity for the demand at the time. We stopped shooting up sattelites, but we developed much better wireless technologies (e.g. MIMO) down on earth, and SpaceX now has the means to deploy those in space and undercut the competitions offerings that is still being used heavily for specific use cases (e.g. broadcasting, marine, etc applications) It doesn't even have to be cheap, it just has to be cheaper than the competition. It's not quite world changing, but it's still a massive business (i guess) and would provide spaceX with some steady revenue stream. If it eventually becomes cheap enough for mass market that's just icing on the cake. Also note that any competition also will have to pay SpaceX for deployment, so SpaceX wins no matter what.
- planteen 10y agoIt's nowhere near that expensive (dollars per kilobyte). I used the GlobalStar network on a project. The bigger cost for overage is 0.35 cents per second on data. The effective rate for a scp transfer (e.g., after all overheads) is about 750 bytes/ second. So you are looking at less than half a cent per KiB. http://www.globalstar.com/en/index.php?cid=1470 http://www.globalstar.com/en/index.php?cid=1470
- sly010 10y agoI didn't know that. I got my numbers from [0]. Perhaps dollars are an overstatement, but your numbers are also for a best case scenario, when you have an application where you need to send data infrequently, in bulk, in an area with good coverage (not at sea) and no guarantees. [0] http://www.rock7mobile.com/products-rockblock-plus.php http://www.rock7mobile.com/products-rockblock-plus.php
- robotresearcher 10y agoYou're missing the current very high cost of crappy satellite bandwidth. This isn't competing with downtown fibre, it's competing with current solutions for way-out-of-town stuff, which are either very expensive or very low bandwidth or both. Source: am outdoor robot researcher.