
Elon Musk said SpaceX's multi 1000 satellite Internet service will be IP-less - deadcoder0904
https://twitter.com/elonmusk/status/967712110661615616
======
imtringued
The headline is completely misleading. The transport layer won't use IPv6.
It's like saying ethernet doesn't use IPv6. That's unsurprising.

~~~
petee
Beyond that, there is entirely no substance here - unless he wants to release
details, this is non-news, just more business fluff - "Ours will be even
better. It'll be huge. The best. Others, so sad"

"And if its hacked, we'll just patch the firmware. So easy."

~~~
kakarot
I'd be bragging about my satellite fleet, too. The guy's only human.

~~~
treebeard901
Do you have a source for this?

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staltz
Hi, I'm andrestaltz who Elon answered on Twitter. Like others have mentioned
here, it seems like Elon is referring to the link layer between the
satellites. "Peer-to-peer" probably meant "without a network switch".

I wish I had originally tweeted "... peer-to-peer connections within Starlink-
only customers" because I was actually interested in knowing if Starlink could
be like ZeroTier. [https://zerotier.com/](https://zerotier.com/)

~~~
deadcoder0904
Sorry I'm the OP. I just stole the title from Reddit for some easy karma
because I couldn't understand all the jargon. PS - Admire both your work <3

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walrus01
Musk is talking about the OSI layer 1 and layer 2 of the satellite network,
which by definition needs to be something unique and custom. Nobody has ever
built a LEO dual-satellite-CPE make-before-break architecture before. The
closest thing is the o3b architecture which is intended for very large, costly
customer terminals. This will still speak ipv4 and ipv6 just fine.

To gain a better understanding of why this needs to be totally
unique/custom/proprietary, it is helpful to first have a thorough
understanding of current high capacity dedicated geostationary orbit based
systems (1:1 SCPC/MCPC with dedicated kHz) and various shared-bandwidth VSAT
type systems (TDMA timesliced architecture between one large earth station,
one piece of satellite transponder kHz, and a number of N fixed CPE terminals
within the satellite's spot beam.

After understanding current geostationary architectures, dig into the "How"
and "why" o3b was created and has been such a success, and its general system
architecture which is proprietary.

Satellite engineer here: The OSI layer 1/2 needs to be totally custom because
we're dealing with a unique architecture of, just off the top of my head:

a) dual satellite LEO architecture

b) possible satellite-to-earth station trunk links, and satellite-to-satellite

c) CPE terminals that have no moving parts and use phased array antenna
systems to talk to two satellites at the same time. From the stationary point
of view of a rooftop CPE, the satellite that is currently "rising" from the
horizon and will be soon overhead, and the satellite that is currently
overhead and will soon pass out of sight.

d) Densely packed high frequency spot beams on a moving LEO satellite. The
closest thing that's ever been built to this before is again the o3b
satellites, but there are a great deal fewer of them, they orbit much higher,
and have much larger spot beams than these small LEO high-Ka/V-band satellites
will have.

e) Custom indoor modem RF tech to talk to the rooftop CPE and provide a
standard 100/1000 copper ethernet handoff (and possibly integrated 802.11ac
dual band wifi). TDMA timeslicing per CPE and bandwidth allocation - there is
no way that an individual CPE will get 1:1 dedicated bandwidth 24x7x365, the
amount of capacity in an individual spot beam sized area will be oversold
based on standard network architecture principles that most people don't try
to max out the capacity of their circuit 24x7.

~~~
kartickv
For people who're not technical engineers and without the knowledge to
understand all the technical details:

\- Does it make sense to make a phone that acts as a receiver (assuming the
phone is outdoors), because it's one fewer device to buy and power, or does it
bring down the cost significantly to have a fixed unit installed on your
terrace?

\- If we want to provide remote regions with Internet access, would you go
with Starlink or O3b? Would your answer change if the requirement was
affordable internet access, no matter the speed?

\- Under what conditions can Starlink or O3b compete with terrestrial internet
in cities?

Basically, I'm trying to understand the impact these programs might have on
the world, not the technicalities.

~~~
walrus01
This isn't going to be for phone sized things. it'll be more like the size of
a direcTV dish but in a very different shape. The system design and technical
requirements to have something that moves around and is handheld is very
different than a fixed CPE that's aimed upwards.

For your second question, both are suitable, but in different markets. O3B is
intended to replace high cost Ku and C-band transponder capacity for telecoms
and ISPs that are in a place economically impossible to reach with PTP
microwave or fiber. The smallest terrestrial o3b terminal is a pair of 1.8
meter motorized tracking antennas semi-permanently installed on concrete pads.
O3B gives an ISP one big fat pipe back to the terrestrial internet in
somewhere with good connectivity, and then that ISP can distribute service
around their region using whatever technology they want to use, or have access
to (PTP microwave, point to multipoint, fixed LTE, DOCIS3.0, various types of
FTTH, etc).

o3b only functions at latitude +/-45. Starlink and similar systems will be in
polar orbits, so with network architecture for satellite-to-satellite relay,
there is the possibility of truly global coverage (as Iridium service works
equally well at the north pole, in remote parts of Nunavut, at the south pole,
in Tierra del Fuego, etc).

It will not be competitive in cities against terrestrial based infrastructure.
Given advancements in how much data can be shoved through old copper
(DOCSIS3/3.1, VDSL2 30a, g.fast) and various active ethernet FTTH and GPON
FTTH, those will have much greater throughput. A dozen starlink satellites
will have less aggregate data throughput than what it is possible to push down
two strands of singlemode fiber.

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sly010
It's not "internet" then, it's a communications network. On top of which third
parties will probably implement IP. He also says peer to peer, but perhaps he
just means point-to-point, in which case it will be very similar to existing
satellite communications network, perhaps just more and faster.

~~~
lallysingh
Sounds like something analogous to ATM or whenever frames. The IP layer would
probably start from the satellite transceiver on The customer premesis.

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grondilu
IP is fairly high in the TCP/IP layer stack[1], isn't it? So it shouldn't be
too surprising that a transport layer (or link layer? Not quite sure) does not
use it, should it?

1\.
[https://en.wikipedia.org/wiki/Internet_protocol_suite](https://en.wikipedia.org/wiki/Internet_protocol_suite)

~~~
nsommer
IP is a network layer protocol, it connects two hosts. TCP is a transport
layer protocol, it connects two processes and runs on top of a network layer
such as IP. The link layer connects two links (e.g. your computer and your
WiFi router), examples are Ethernet or 802.11 (even though they also
incorporate management of the physical layer).

What the satellites have to deal with is pysical/link level protocol to send
packets from one to another (and from and to ground stations) as well as a
network level protocol to route traffic inside the SpaceX network.

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gnode
I wonder if the reason here is that the topology of the network will change
rapidly. E.g. as equatorial and polar satellites cross each other, they will
be in direct communication with each other for only brief periods of time.
There are ways to cope with routing changes in IP, but I don't know if it'd be
seamless enough.

~~~
KMag
It's easy to read too much into a tweet, but it sounds like the header size
overhead and number of options are the primary reasons for not using IPv6.

Note also that IPv4 and IPv6 are nearly independent of the routing protocol.

Also, my first job was writing discrete event models of wireless
communications equipment, including a couple satellite models. You'd be
surprised how simple satellites themselves are. A lot of work goes into moving
the complexity from the fragile, expensive, and out-of-reach satellites and
into the ground stations. I wouldn't be surprised if packets weren't at least
partially source-routed, which might very well involve broadcasting GPS-like
tables of satellite orbit parameters.

~~~
gnode
I expect that internet traffic will still travel over the network using IP,
but encapsulated in the SpaceX protocol. I expect translating the headers to
and from IP would not make the protocol "simpler than IPv6", and would not be
justifiable complexity to save a few bytes.

I think this "simple" protocol is just to simplify routing, and allow non-IP
traffic over the network (in-band control messages; phone calls?).

~~~
KMag
Looking back at the context, I think you're right. It looks like Elon was just
trying to explain to someone without much networking background that, like
most link layers, they'd be using a link layer more simple than IPv6. He
probably wasn't making a statement about lossy header compression that
discards uncommonly used features.

------
mentos
I am excited about Space and self driving cars but I think this could have
much greater positive effects on humanity. Freedom of the internet could be
the thing that saves this planet when it comes to thinking on a thousand year
term.

------
deweller
So the topography here is:

Individual router <-> satellite mesh net <-> SpaceX router connected to the
internet.

Is there any reason why the protocol between satellites matters? They clearly
aren't aiming for interoperability with other companies.

~~~
walrus01
the protocol and modulation/coding scheme between satellites (for in-space RF
links) matters a great deal, because coding efficiency can vary... If would
have a great deal of protocol overhead and wasted bps if they were to
optimized it to actually speak Ethernet between satellites (eg: to pass
standard 1600B or 9000B frames) versus something that has been designed from
the ground up for a very specific amount of latency, and designed for a
satellite-to-satellite trunk link. However they're breaking up the data also
has to deal with the possible earth station architecture. I have not
personally seen the design of a Starlink satelilte, but the concept is
basically similar to a very small version of o3b.

Each satellite will have basically three different RF setups on it:

1) L or S-band TT&C (tracking, telemetry and control). This is the admin and
OOB management for the satellite and some of the frequencies can be seen in
SpaceX's recent FCC filing, with earth stations in the Seattle and Los Angeles
area.

2) Multiple Ka/V-band or other multiple spot beam antennas aimed straight
down, serving CPEs.

3) There will be at least two dedicated high capacity dish antennas per
satellite aimed at large, high capacity fixed earth stations (2.4 to 5 meter
size) operating in the Ka-band or higher. The earth stations will need to be
geographically distributed around the globe at various fiber IX points,
similar to how o3b has done things now, so that the satellite-to-satellite
trunk links can take the fewest possible number of hops before downlinking to
the terrestrial internet. The more medium sized earth stations the better,
because it increases the chance that a link to an individual CPE can take a
bent-pipe path rather than traveling through multiple satellite-to-satellite
hops. For example a CPE in far rural Wyoming, and a satellite passing over the
general area of Wyoming, might be able to "see" a 3.0m sized high capacity
earth station located near fiber in Cheyenne. Data from CPE, up to satellite,
down to Cheyenne, one hop.

------
nugga
If they can make it so you could get a cheap subscription to starlink, without
needing your own receiver, to route your udp traffic I would pay for sure.
Since it's going to be a LEO constellation the pings will be crazy low round
the world and you could play US-EU games at under 100 ms even if you had to
have a hop or two via fiber to the nearest starlink connected hub.

------
CamTin
So is he not planning on offering Internet access then? Just transit to other
Starlink stations? Presumably even that would allow somebody to offer a "real"
ISP on top of this service with a ground station and then peering to the
Internet. Still, paying for Starlink and then separately paying for a
Starlink-Internet bridge isn't the greatest consumer experience.

~~~
taneq
Well presumably he'd have peering arrangements in a few key places, it just
means that within the network your data would go relatively directly instead
of satellite-hopping to a central server and then back out.

------
madez
I don't think the market for satellite Internet is only where other services
don't provide fast enough internet. Of course, the technology of glass fiber
in the ground can't be beaten qualitywise, but glass fiber can more easily be
controlled by your ISP and your government, unlike satellite internet. _If_
SpaceX manages to provide unfiltered, net neutral, cheap internet, I'd
consider getting it to complement my current connection.

~~~
jsjohnst
> but glass fiber can more easily be controlled by your ISP and your
> government, unlike satellite internet.

What would lead you to believe that? The reality is that the reverse is true,
satellite internet is more heavily scrutinized as it’s far easier to intercept
and very few companies are doing it.

~~~
madez
On my earthbound connection my government can influence the ISP, but how is
the government of [insert-autocratic-country] here supposed to control what
its citizen do over satellite internet?

I assume that all communication to, in, and from the satellite network is
secured by cryptography to prevent eavesdropping.

------
zeristor
Is this a case of doubling down, whilst SpaceX waits for the demand to launch
satellites at the lower price grows.

Its one thing to be able to launch satellites far more cheaply than other
companies, perhaps the economics demands certain number of launches a year to
keep capacity up and price down?

The question is what happens when they launch all 1000 satellites?

~~~
mrep
> The question is what happens when they launch all 1000 satellites?

The plan is for 12,000 satellites and they are only designed to last a few
years and then be replaced. This keeps launch rates constant, allows them to
make much larger use of economies of scale by having that many satellites, and
to constantly improve speed by building the new satellites with state of the
art technology.

[https://en.wikipedia.org/wiki/Starlink_(satellite_constellat...](https://en.wikipedia.org/wiki/Starlink_\(satellite_constellation\))

~~~
zingmars
That's a lot of satellites. What are they going to do with the deprecated
ones?

~~~
lostapathy
LEO orbits degrade fairly steadily - without constantly boosting them back up
they will de-orbit on their own. Because of that, they won't leave space junk
in orbit.

From how they describe these satellites, they will be small enough to burn up
in the atmosphere and not cause any issues on the ground either.

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sailfast
I am excited for any option that would allow me to actually choose my provider
as a consumer, rather than rely on embedded infrastructure. This is super
exciting for that reason and many others (potential breaking national control
of a global connection, for one) and I can’t wait to see how it progresses.

------
devit
Is there an estimate on the magnitude of the maximum total bandwidth
achievable with a LEO satellite, both for a smartphone client and for a fixed
home antenna?

How far would it be to 4G and gigabit fiber respectively?

~~~
patrickaljord
It's not the bandwidth I'm curious about, I'm wondering what the latency will
be like. Satellite connections usually have bad latency because of obvious
physics laws limitation. This can be bad for real time apps. Still great for
most web applications though.

~~~
simonvc
These are MEO sats, not Geo stationary at 30,000km.

The round trip for these will be about London to Edinburgh and back and we
video conference that distance all the time.

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Quarrelsome
How would the tech work exactly? Would this make it more difficult for the
government to tap into connections as one could technically (outside of an
ISP) jack straight into that network?

~~~
derekp7
I would imagine that those governments would make it illegal for people to own
the receiver equipment. Just like some (in the past) have made it illegal to
own a shortwave radio.

~~~
john_minsk
Agreed. Or Musk will have to agree to filter traffic.

------
220V_USKettle
IPX/SPX?

~~~
walrus01
well, we can play Quake 1 across it...

------
Numberwang
For those of you in the know here. Is this a realistic project/enterprise he
is working on?

Seems both costly to deploy that many satellites and risky in the sense that
you can't count on getting a lot of customers. Especially with the new super
speedy 5G networks and so on.

~~~
sho
Hell of a lot of places without 5G, or _any_ , mobile internet. Don't forget
aviation and to a lesser extent maritime either. People love their onboard
wifi.

Owning the launch platform could mean that he's able to significantly undercut
current players, although funnily enough soon-to-be competitor Iridium
recently launched a whole bunch of new satellites using SpaceX. Good position
to be in when your competitors are dependent on you!

There are certainly challenges, though. Latency is a huge problem with
satellite internet, for obvious reasons. I'm not sure what the intended
bandwidth is but satellite will always "feel" slower than mobile data of
equivalent speed. The fact that it's a mesh network with who knows how many
"hops" presumably makes it even worse. So it won't ever compete with mobile,
not even 3G probably.

~~~
jsjohnst
1) Starlink will be in LEO around 800mi up unlike most communications
satellites (like HughesNet) which are in geostationary orbit at ~22,200mi.
Expect 25-35ms latency as compared to 600+.

2) due to having a lot more birds in the air at lower altitude with newer
tech, they should be competitive with 5G networks speed wise as compared to
existing satellite internet.

Edit: fixed distance typo for HughesNet

~~~
sho
Huh. That's really close.

Your numbers are off though. Firstly it's ~40ms up to the bird if it's right
above you, then 40 down to the base station if it is next door to your house.
If it's on the other side of the world and has to travel around the whole
mesh, add a hundred ms at best. Then from the base station to the destination
- which could be anywhere in the world, and back, then back up to the bird,
then back down to you.

It's not going to be 40ms, probably not even 400ms, and there is _no way_ it
will be competitive with mobile 5G.

It might not even be competitive with the geostationary birds for accessing
nearby hosts. 22k miles is ~120ms, so 240ms round trip - because the base
station is generally pretty nearby. Say ~20ms both ways for in-country ping
and you're looking at 520ms -ish total, which is reasonably consistent with my
experience using it from the Solomon Islands.

Huawei's saying 1ms to the tower for 5G!

~~~
bchallenor
I make it 4ms [1], not 40ms.

[1]
[http://www.wolframalpha.com/input/?i=800mi+%2F+speed+of+ligh...](http://www.wolframalpha.com/input/?i=800mi+%2F+speed+of+light)

~~~
sho
* facepalm

Too late to edit. Misplaced the decimal point. Should have noticed that if 22k
is 120, 800 can't possibly be 40. Duh.

Still, the actual latency is going to be very dependent on the distance to the
base station. If it's nearby then shit, yeah, that will be within 20ms of 5G.
Point conceded @jsjohnst.

~~~
jsjohnst
It doesn’t make sense to bounce a signal over North America / Europe / etc all
around on the mesh. The best course is to send it to the ground almost
immediately (aka <2-3x max) for those areas as otherwise you’re wasting
bandwidth. But over the Pacific Ocean it makes complete sense as adding a
ground station in the middle of the ocean doesn’t make sense and even if you
did, you still have latency to nearest server farm.

So yes, my point still stands for the majority use case.

Also, to be clear, I was making following claims:

1) bandwidth on par with initial 5G deployments (aka up to 1gb/sec offering)

2) Latency on par or better than existing LTE networks.

~~~
sho
Yeah, my skepticism was definitely misplaced. I guess I didn't internalise
just how _close_ that is! Mea culpa.

This could open astounding possibilities if the prices are set within any kind
of consumer-affordable level. I'm fairly interested in going on some long sail
journeys, for example, but the total lack of connectivity (without a ruinously
expensive and hence rare conventional satphone) gives me a lot of pause. What
if something happens at work, or worse yet with my family, and i'm literally
uncontactable, hundreds of miles offshore somewhere for a week? I know that
for some people that's the point, but I wouldn't be able to stop worrying
about it.

If your prognosis is correct then not only might it become feasible to be
contactable on a boat for a reasonable outlay, you might even have friggin'
broadband. For me and I suspect many others that's a very exciting idea.

------
qaq
I think people are ignoring one very lucrative application Military.

~~~
gnode
Not that I don't think it will be useful for this. But Iridium is already
offering LEO satellite service for low-latency government / military use.

------
gagabity
How will this actually work? Will individuals be able to tap into it skipping
the local ISP? I also wonder how the issue of government censorship/control be
dealt with in various countries around the world.

~~~
mtgx
It would be nice if it used unlicensed spectrum in all countries, and then all
anyone would have to do to connect to the SpaceX internet is get their hands
on a modem that supports it. That would be very liberating for many countries,
and I'm not sure there would be much the local governments could do other than
throw a tantrum. They could start requiring a license for all free spectrum,
but that would have non-insignificant consequences for their local economy,
too.

~~~
jsjohnst
> It would be nice if it used unlicensed spectrum

If you are talking about the bands I think you are referring too (2.4/5ghz)
then you aren’t considering the implications. To send a signal from ~800mi
away on those bands, you’ll need to be radiating with so much power that
you’ll effectively destroy any terrestrial usage of those bands. Literally
your Wi-Fi won’t work anywhere on earth due to the channel congestion / noise.

------
zerostar07
what are the ping times for satellite networks?

~~~
gizmo385
Depends on the network. The current satellite internet systems all use
satellites parked in a geosynchronous orbit. This means that ping times are
measured in the hundreds of milliseconds in most cases.

The satellite network that Musk is talking about uses a very large web of
satellites in low Earth orbit, which would mean ping times of less than 100
milliseconds.

