What a fascinating way to fight a totalitarian crackdown. The article doesn't seem to talk about its feasibility against the government though. Is there no way they could stop it, bar actually damaging people's satellite dishes?
can satellite dishes be redesigned such that they don't just have a directional peak in sensitivity, but also a controlled suitably low maximum sensitivity in other directions?
or is jamming typically done from drones / airplanes to jam a slanted conical region below them?
when they physically remove dishes, do they discover them typically visually (so they just need to be hidden in a RF transparent box say plastic) or do they already use direction finding on local oscillators?
You could design a receive only satellite dish with side shielding, even up to the point of making it technically equivalent to an ETSI class 4 antenna for licensed microwave systems, but it would look considerably different (like a drum with tall walls) and would cost a great deal more.
in general this is a very cost sensitive market if you go to a big city in pakistan, afghanistan or iran and look at the $100 satellite dishes with LNBs all over the roofs.
That is a good point. I was being overly generous by far on the actual dish cost, and including the cost of cabling and a basic receiver set top box. But building a jam resistant rx only dish would still have significant economic challenges.
Assuming they encode it like a tv channel, it would be multiplexed on one transponder with roughly 9 other tv channels. So if the government tried to jam or block it, they would zap a bunch of legit television.
I don't know if the uplink is in Iran. If so, it would be trivial to shut it down.
In the case of "toosheh", there is no uplink, it's a one way transfer of curated content in a compressed archive. They're using leased Ku band transponder space on a geostationary satellite generally above the region, same as commercial TV channels.
You're describing a unidirectional data flow for Toosheh which makes sense but in the article it mentions payloads of videos from all over Iran. From what I've read VPNs were also shut down so how did the Iranians output videos? Was it purely journalists that had access to outside networks?
Thankfully up until recently Iran's attempts at a great firewall have not been as successful as China. There's "private" ISPs in Iran but they're all required to singlehome to the state owned ASN, which operates all of the transit links to the outside world.
From a network engineering perspective I would say that Iranian government acumen at running advanced DPI systems for automated detection/blocking of VPN traffic on a per-flow basis is much less advanced than China's. The most talented Iranian network engineers can generally emigrate somewhere else and get paid a better salary to not work on projects they find personally distasteful.
Tons. Schools in Iran are smaller and more numerous. I did a little back of the napkin math and I estimate there are more than 4000 high schools in the City of Tehran, more than 6500 if you count the schools in the entire Province of Tehran.
Also, why would they put him in jail? I think you are greatly overestimating the level of political repression in Iran. If they wanted to put people in jail for using VPNs or leaving private voicemails, half the population would be in jail.
Iranian guy said to us that VPN is not forbidden in Iran (only internet is filtered). Actually guy in airport who sold us sim-card shown which VPN app to use :)
Might be useful to add 'diaspora' too, since it can be used for any group of people who share a common origin:
"A diaspora (/daɪˈæspərə/) is a scattered population whose origin lies in a separate geographic locale. Historically, the word diaspora was used to refer to the involuntary mass dispersion of a population from its indigenous territories, in particular the dispersion of Jews."
And there's Othernet providing a somewhat-Toosheh-like service all over the place. It's unidirectional, but carries an interesting mix of content, which accumulates on a receiver that then serves it out over local wifi. It's very BBS-like, and I wish it had more BBS functionality (local file storage for the folks using the same unit).
I had a lot of fun with it back when they were running L-band. Since the move to Ku-band, I had no luck getting a lock, tried a few more LNBs, still nothing, decided I'd try again with a dish, and haven't gotten around to it.
Residents of Bali, Indonesia still use a type of sneakernet to get around ISP throttling and slow performance. (Censorship is rare in Indonesia, aside from Reddit.)
Typically 2 or 3 middle-aged male friends will go to the fastest internet cafe on the island with SD cards or USB hard drives and download as much as they can, then return to their village and share.
With Starlink in full operation, it should be teoretically possible to create such unidirectional service with much bigger bandwidth. Not just with Iran, but China as a target.
Blocking such signals from reaching the earth would be a challenge even for China.
China (or some other totalitarian regime) would probably threaten to shoot down the sattelites if Starlink didn't let the Chinese government do man-in-the-middle.
That's fairly absurd, such an action would essentially be declaring war. I don't see it happening, Starlink simply won't sell the devices in China and that's it.
I thought that this alternative is too obvious to mention. My point was that providing internet access in China without letting them MITM it would effectively be a war declaration.
Satellite phones ($500 and up for the device, $40 and up per month for the subscription, $1 and up per minute of use [1]) are out of reach for ordinary Chinese (GDP per capita in 2020 is about $10k) [2]. A better comparison would be China's handling of VPNs.
Satellite phones are out of reach like meth and online political dissent is for the Chinese, yet still everywhere.
Regardless of mispricing in your links for the average mainlander (they make most satphones/data receivers) hundreds of millions of people in China could still afford it at the prices quoted.
This isn't some small Finnish town we're talking about, it's 1/5th of every person alive on Earth.
> hundreds of millions of people in China could still afford it at the prices quoted.
Maybe (I would be more comfortable with a claim that tens of millions can afford them), but they don't have them. Why not? Because the affluent "elite" largely consists of the CCP's 91 million members. They are the winners in the current system, and therefore the least likely to oppose it.
What China fears and cracks down on is free flow of information to and between the masses of ordinary Chinese.
> This isn't some small Finnish town we're talking about, it's 1/5th of every person alive on Earth.
Moving the goalpost there. 1/5 of Earth's 7.8 billion is 1.6 billion, not your "hundreds of millions".
Well, yes, of course that comes to mind, but between the threat and the actual shooting, there is a very significant decision that could lead to a nuclear war.
I think that they, among the threats, would start working on jamming the signal somehow. A much safer option.
Three chances that any major power hot war doesn't produce Kessler Syndrome: slim, fat, and none.
(Not that we'll necessarily be around to care. I have no idea if ICBMs still use celestial navigation, but we'd have to mess up pretty badly to no longer have stars...)
Starlink will be ~ten thousand pieces of metal, all on different orbits.
Ignoring the whole "act of war" thing, everyone in this thread is dramatically underestimating how difficult it would be to shoot down a constellation that large. We can barely shoot down one satellite, at a cost of somewhere around a few million dollars.
SpaceX is launching 60 at a time, while each shoot down would be a fairly complicated logistical nightmare.
Just put a big air-baloon over each city(or even much larger areas), positioned aroung the direction the satelite is, and you can easily send a similar, but more powerful signal than the satellite and jam the reception.
Why iran doesn't do this is an interesting question.
Reminds me of the cuban sneakernet "el paquete semanal". Should be possible to use sticks and sdcards that are passed around for quite async very slow encrypted communication or messaging boards.
Devices like the LoRa QWERTY Messenger by Scott Powell or one of the LoRa extensions for smartphones people are building, could be useful for communication, too.
I really like the idea of the LoRa devices. However, I worry about them drawing attention to users and causing further issues. An oppressive government will eventually realize they are in use and start tracking down their locations.
What type of measures could be done to limit attributing the LoRa device to individual users?
I spent some time researching a similar idea I had about using a mpeg TS stream to encapsulate arbitrary data and then use a SDR to broadcast it over regular DVB-t frequencies. I didn’t find a lot of information on how to encode/decode the stream, though. I also haven’t found many technical details on how they are doing it in this case. When I first read the article I was hoping it was an open source project, but alas I can’t find anything about this either. Anyone have any hints/pointers?
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[ 0.18 ms ] story [ 95.1 ms ] threador is jamming typically done from drones / airplanes to jam a slanted conical region below them?
when they physically remove dishes, do they discover them typically visually (so they just need to be hidden in a RF transparent box say plastic) or do they already use direction finding on local oscillators?
https://aviatnetworks.com/tag/class-4-antennas/
https://www.commscope.com/blog/2015/the-benefits-of-class-4-...
in general this is a very cost sensitive market if you go to a big city in pakistan, afghanistan or iran and look at the $100 satellite dishes with LNBs all over the roofs.
I don't know if the uplink is in Iran. If so, it would be trivial to shut it down.
Edit: Apparently the uplink is in the UAE.
From a network engineering perspective I would say that Iranian government acumen at running advanced DPI systems for automated detection/blocking of VPN traffic on a per-flow basis is much less advanced than China's. The most talented Iranian network engineers can generally emigrate somewhere else and get paid a better salary to not work on projects they find personally distasteful.
How many people can that describe?
I assume this individual is now in jail.
Tons. Schools in Iran are smaller and more numerous. I did a little back of the napkin math and I estimate there are more than 4000 high schools in the City of Tehran, more than 6500 if you count the schools in the entire Province of Tehran.
Also, why would they put him in jail? I think you are greatly overestimating the level of political repression in Iran. If they wanted to put people in jail for using VPNs or leaving private voicemails, half the population would be in jail.
- home distillation is illegal
- rich kids can get slaps on the wrist for what poor kids get in serious trouble over
"Iranians abroad or Iranian diaspora are Iranian people living outside Iran and their children born abroad."
https://en.m.wikipedia.org/wiki/Iranian_diaspora
Chinese diaspora, African diaspora, etc
"A diaspora (/daɪˈæspərə/) is a scattered population whose origin lies in a separate geographic locale. Historically, the word diaspora was used to refer to the involuntary mass dispersion of a population from its indigenous territories, in particular the dispersion of Jews."
I had a lot of fun with it back when they were running L-band. Since the move to Ku-band, I had no luck getting a lock, tried a few more LNBs, still nothing, decided I'd try again with a dish, and haven't gotten around to it.
I should try again, and soon...
Typically 2 or 3 middle-aged male friends will go to the fastest internet cafe on the island with SD cards or USB hard drives and download as much as they can, then return to their village and share.
Blocking such signals from reaching the earth would be a challenge even for China.
[1] https://www.bluecosmo.com/satellite-phones
[2] https://data.worldbank.org/indicator/NY.GDP.PCAP.CD?location...
Satellite phones are out of reach like meth and online political dissent is for the Chinese, yet still everywhere.
Regardless of mispricing in your links for the average mainlander (they make most satphones/data receivers) hundreds of millions of people in China could still afford it at the prices quoted.
This isn't some small Finnish town we're talking about, it's 1/5th of every person alive on Earth.
Maybe (I would be more comfortable with a claim that tens of millions can afford them), but they don't have them. Why not? Because the affluent "elite" largely consists of the CCP's 91 million members. They are the winners in the current system, and therefore the least likely to oppose it.
What China fears and cracks down on is free flow of information to and between the masses of ordinary Chinese.
> This isn't some small Finnish town we're talking about, it's 1/5th of every person alive on Earth.
Moving the goalpost there. 1/5 of Earth's 7.8 billion is 1.6 billion, not your "hundreds of millions".
I think that they, among the threats, would start working on jamming the signal somehow. A much safer option.
They would simple disallow business between you and the satellite operator. Nothing easier than that.
they're able to go to the moon, so i don't think destroying a piece of flying metal in orbit would be a problem
Starlink being an American military asset among others, the US would probably respond by destroying all Chinese hardware in space.
Now what?
(Not that we'll necessarily be around to care. I have no idea if ICBMs still use celestial navigation, but we'd have to mess up pretty badly to no longer have stars...)
Ignoring the whole "act of war" thing, everyone in this thread is dramatically underestimating how difficult it would be to shoot down a constellation that large. We can barely shoot down one satellite, at a cost of somewhere around a few million dollars.
SpaceX is launching 60 at a time, while each shoot down would be a fairly complicated logistical nightmare.
Just put a big air-baloon over each city(or even much larger areas), positioned aroung the direction the satelite is, and you can easily send a similar, but more powerful signal than the satellite and jam the reception.
Why iran doesn't do this is an interesting question.
https://en.wikipedia.org/wiki/Sneakernet
https://hackaday.io/project/174019-lora-qwerty-messenger
I once read something about a system people were using in remote african villages to sync data via usb sticks but i can't find it.
TIL the idea of hilarity ensuing via TEU abuse was not innovative: https://www.darpa.mil/program/tactically-expandable-maritime...
What type of measures could be done to limit attributing the LoRa device to individual users?
How would one go about setting up something similar?