[HN Gopher] A technical look at Iran's internet shutdowns
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       A technical look at Iran's internet shutdowns
        
       Author : znano
       Score  : 86 points
       Date   : 2025-07-13 16:45 UTC (6 hours ago)
        
 (HTM) web link (zola.ink)
 (TXT) w3m dump (zola.ink)
        
       | naryJane wrote:
       | I appreciate the final paragraphs which suggest a solid method
       | for those inside the country and under this oppressive regime to
       | remain connected without surveillance. I wonder how many are up
       | to this, and what active resistance or movements inside the
       | country look like these days.
        
         | justusthane wrote:
         | Does it, though? It doesn't mention whether or not hosting your
         | own encrypted messaging platform is illegal, what the
         | repercussions are, or how to hide that you are doing so.
         | 
         | I found the whole article to be unfortunately light on both
         | technical details and practical details, and certainly wouldn't
         | suggest that anyone use it as a guide.
        
           | Vulturus wrote:
           | I was wondering myself, if it isn't very dangerous to host
           | those kinds of services in an opressive state such as Iran?
           | Hosting a site on Iranian IPs certainly sounds easy to track
           | and I'm sure a Starlink receiver also makes substential RF
           | noise. Anyone has any information about how likely is the
           | Iranian government is to shut down such a site/service? Also,
           | doesn't encrypted traffic in general (like Matrix servers)
           | fall into this category?
        
           | immibis wrote:
           | > whether or not hosting your own encrypted messaging
           | platform is illegal
           | 
           | Matrix isn't meaningfully encrypted, so it's mostly
           | irrelevant, hooray!
        
         | joecool1029 wrote:
         | Synapse sucks to run and it doesn't minimize metadata
         | collection. It's not a great choice unless you're running it
         | outside the country where they can't seize the server (but then
         | you have all the problems of not being able to access it when
         | the country is cut off from the rest of the world). It's a pig
         | on resources which means it has to be run on hardware that can
         | handle it, barely runs on SBC's.
         | 
         | Other stuff is weird in their post and suggests they are
         | speaking for Iranians without actually knowing any online. I
         | know a few from the Cellmapper community and SMS is very much
         | not expensive. 1000 SMS costs around 0.03USD worst case:
         | https://irancell.ir/en/p/3771/tariffs-and-voice-packages-en
         | 
         | Finally it's not really that Starlink uses proprietary
         | encryption that's special. They can use any sort of common
         | encryption standard and there's not much Iran can do but locate
         | and seize the terminal since they don't have the keys to it. I
         | imagine at some point they were start looking for signal
         | emissions in known Starlink bands and use that to locate
         | terminals. Allegedly Russia has a detection system 'Kalinka'
         | already built: https://www.space.com/space-
         | exploration/tech/russia-and-chin...
        
       | RiverCrochet wrote:
       | I wish this article went into more details on what the "National
       | Information Network" is. I would guess it's at least a set of
       | nationally managed DNS servers that will always resolve national
       | IPs even if upstream global DNS is cut off.
       | 
       | Looking at a bigger picture though, honestly I think we're seeing
       | the end of the raw global Internet for the masses. 20 years ago,
       | it seemed impossible, but here we are.
       | 
       | It's simply not going to be possible to meaningfully use the
       | Internet unauthenticated and unapproved in a few years. Costs to
       | reach mass audiences online will increase until only the big
       | players can do it, and it'll be their platforms or nothing.
       | There's going to be no room for anything that those with millions
       | and billions of dollars don't want or can't make money off of in
       | some way.
       | 
       | Overall, this makes me want to reduce the role of the Internet
       | and tech in my life. I don't need the fastest data plan, latest
       | PC, newest phone, or whatever AI trend is hot to use the apps I
       | need for daily life or to line up events and meetings with others
       | that I actually know.
        
         | alephnerd wrote:
         | > more details on what the "National Information Network" is
         | 
         | Some sources [0][1]
         | 
         | > I would guess it's at least a set of nationally managed DNS
         | servers that will always resolve national IPs even if upstream
         | global DNS is cut off.
         | 
         | Yep. Along with an entire ecosystem of domestically created and
         | regulated search engines, DPI, centrally managed certs, AV,
         | networking backbone, etc.
         | 
         | It's similar in intention to the Great Firewall in China,
         | except much more restrictive.
         | 
         | Imagine corporate IT restrictions and posture being deployed
         | nationwide on all endpoints, that's how these kind of
         | initiatives tend to architected.
         | 
         | SSE/Zero Trust, DPI, Cert Mgmt, etc are all dual-use, and it's
         | essentially a logistics and organization problem.
         | 
         | [0] - https://apps.dtic.mil/sti/pdfs/AD1107324.pdf
         | 
         | [1] -
         | https://www.article19.org/data/files/medialibrary/38316/The-...
        
         | hexomancer wrote:
         | I wrote a blog post which hopefully clears up the "National
         | Network": https://ahrm.github.io/jekyll/update/2025/06/20/iran-
         | interne...
         | 
         | It is way more than just DNS.
        
           | alephnerd wrote:
           | Is Google's AI Mode working? That might solve the problem you
           | mentioned.
        
             | hexomancer wrote:
             | Well, the internet is not national anymore (for now!), but
             | isn't Google AI Mode US only? Anyway, the only google
             | service that did work at that time was google search as far
             | as I know nothing else worked (no gmail, maps, etc.).
        
               | alephnerd wrote:
               | Ah - I didn't realize Google AI Mode is US Only!
               | 
               | > the only google service that did work at that time was
               | google search as far as I know nothing else worked (no
               | gmail, maps, etc.)
               | 
               | Yea, sounds like they resorted to a hard whitelist. How
               | were other Internet services impacted in Iran? My
               | understanding is payment is increasingly tap-to-pay or
               | via digital wallets within Iran? How was that impacted
               | during the shutdown?
        
               | hexomancer wrote:
               | Well, Iran is sanctioned as fuck, so no global payment
               | system works in Iran anyway. All the payment systems used
               | by Iranians are local so they work even in national
               | internet.
        
               | alephnerd wrote:
               | Yep! What I meant was during the recent conflict, was the
               | domestic payment system working? How brittle or robust
               | was it during that, especially given that my
               | understanding is that Iran has transitioned to a cashless
               | society?
        
               | hexomancer wrote:
               | Yes, it was working at least in my experience.
        
         | joecool1029 wrote:
         | > Looking at a bigger picture though, honestly I think we're
         | seeing the end of the raw global Internet for the masses. 20
         | years ago, it seemed impossible, but here we are.
         | 
         | This is defeatist. You're probably right 'for the masses' but
         | there will always be those networking and collaborating and
         | bypassing whatever restrictions get put in place. I have online
         | contacts in 'firewalled' regimes that use v2ray/shadowsocks or
         | whatever the thing of the now is to get around the
         | restrictions.
         | 
         | There's a ton of cheap tools now that can be used for running
         | local or citywide networks, hams have their own packet radio
         | stuff. There's now all those new LoRa networks that only really
         | popped up in the past few years.
         | 
         | What I'm trying to say is the stuff is there and it's
         | accessible, but it's only going to be a minority of people that
         | use it just as it's a small minority that comments on posts
         | like this (people like us) and even smaller yet again that
         | write content on how to do it and create those tools to begin
         | with. But it has always been this way....
        
           | ZoomZoomZoom wrote:
           | > What I'm trying to say is the stuff is there and it's
           | accessible, but it's only going to be a minority of people
           | that use it
           | 
           | Exactly. This is why the tech has to be made resistant to
           | surveillance and censorship by default. Until usage of
           | alternative connectivity and circumvention methods sticks out
           | as a sore thumb (turns out, for most tools it does), it
           | applies a constant pressure on anyone under oppression to
           | stop, increasing the risks for those who continue to use
           | them.
        
           | mschuster91 wrote:
           | > hams have their own packet radio stuff
           | 
           | We got basically three different things. First we got APRS,
           | mostly used for position reports (go on aprs.fi for a map).
           | That is pretty nice but unusable for anything more than a SMS
           | worth of things, and you need repeaters and not just internet
           | gateway collectors to actually have something that's
           | resilient.
           | 
           | Next thing is AX25, the technical foundation behind APRS. Yes
           | you can use it to create actual data links, but it's about
           | modem speeds so virtually useless outside of toying around.
           | 
           | And finally there is HamNet but it's line of sight based and
           | not cross routed to the internet, and identically to all
           | things ham radio, encryption is banned by law.
           | 
           | And on top of that, you can expect regulatory agencies to
           | crack down on ham radio fast and hard, should it be used for
           | political dissency motives at scale. It's already against ham
           | practice to talk politics, especially with people in
           | repressive countries - we don't want _more_ countries other
           | than Yemen and North Korea to just blanket ban ham radio.
        
             | swores wrote:
             | Am I right to assume that it's easy to locate the source of
             | ham radio signals?
             | 
             | i.e. if there's a blanket ban, can you use your radio
             | hidden in your house or can the government easily find out
             | that the user they've noticed on the airwaves is located
             | there and knock down your door?
        
               | ridgeguy wrote:
               | It's very easy, has been for a long time. See the story
               | of Israeli Eli Cohen, an operative in Syria.
               | 
               | https://en.wikipedia.org/wiki/Eli_Cohen
        
           | Ray20 wrote:
           | >there will always be those networking and collaborating and
           | bypassing whatever restrictions get put in place.
           | 
           | I don't think so. It's just a question of the severity of the
           | punishment for violating regulations. A couple of small fines
           | for an unlicensed networking and collaborating - and there
           | will be no one left.
           | 
           | >There's a ton of cheap tools now that can be used for
           | running local or citywide networks, hams have their own
           | packet radio stuff.
           | 
           | The issue has never been in the technical plane. The
           | equipment for building and operating networks has become
           | dozens of times more accessible over the past couple of
           | decades. The problem is in the increasing number of
           | regulations that purposefully lock all clients into a few
           | select controlled service providers. They have a goal and
           | they have the tools to achieve it, so it's only a matter of
           | time before they reach the minority of network-enthusiasts.
        
           | rs186 wrote:
           | Live in China/Iran for a few years and see if you would still
           | post this same comment.
        
         | one-note wrote:
         | The only way to have global uncensored sharing of information
         | is shortwave radio. Always has been, always will be.
        
           | LocalH wrote:
           | Triangulation exists to locate such stations
        
             | one-note wrote:
             | Did I say untraceable?
             | 
             | You'll be found on the internet too btw. But far more
             | easily.
        
         | mensetmanusman wrote:
         | Maybe, or Starlink and software destabilize the authoritarians.
        
         | immibis wrote:
         | The current global Internet is an anomaly in space and time,
         | and it's held together by spit, prayers, and the hope the
         | reliability gains from multiple redundant paths outweigh the
         | reliability losses from so many distinct actors being involved.
         | It would be quite easy for any major government to cause major
         | problems in global connectivity. So far, they mostly seem
         | content to only cut themselves off, and the ones with the power
         | to mess up the global net don't seem to want to. But the NSA
         | was diverting a whole lot of intra-Europe traffic via the USA
         | at one time so they could snoop it.
        
       | ZoomZoomZoom wrote:
       | > WireGuard uses UDP and a small handshake footprint, making
       | detection and blocking via DPI harder.
       | 
       | Not quite true. Wireguard is already actively detected and
       | suppressed if necessary. There's already a fork that employs
       | basic changes to improve the protocol in this regard. AmneziaWG
       | was shown to be more robust to detection for now.
       | 
       | https://docs.amnezia.org/documentation/amnezia-wg/
       | 
       | Too bad managing WG is such a pain and Tailscale/Netbird don't
       | support this protocol yet. The following two issues need
       | attention:
       | 
       | https://github.com/tailscale/tailscale/issues/10696
       | 
       | https://github.com/netbirdio/netbird/issues/1096
        
         | dongcarl wrote:
         | At Obscura we just tunnel WireGuard over QUIC's unreliable
         | datagram mechanism to make it look like HTTP/3 (for DPI):
         | https://github.com/Sovereign-Engineering/obscuravpn-client/b...
         | 
         | We just upstreamed our patch to quinn-rs that pads Datagrams to
         | MTU: https://github.com/quinn-rs/quinn/pull/2274
        
           | antonkochubey wrote:
           | Some DPIs just flat out block HTTP/3 already.
        
       | xkcd1963 wrote:
       | How do people do this in China?
        
         | mohas wrote:
         | this is much more severe than in China. I've never been
         | completely shut of Internet before. each time one of my servers
         | had access to global Internet. this time no connection
         | whatsoever. I hope people realise that encryption needs
         | transmission, with no wire to transfer data encryption won't
         | help you
        
       | heraldgeezer wrote:
       | Just
       | 
       | enable
       | 
       | configure terminal
       | 
       | router bgp <your-AS-number>
       | 
       | neighbor <neighbor-IP-address> shutdown
       | 
       | end
       | 
       | Easy
        
       | heraldgeezer wrote:
       | >SMS in Iran is unencrypted.
       | 
       | SMS everywhere is unencrypted
        
         | bawolff wrote:
         | Yes, although many people probably don't know the difference
         | between SMS and RCS and use SMS to refer to both.
        
       | bawolff wrote:
       | > IPv4 addresses are limited and constantly reallocated. Most are
       | rented and passed between hosting providers, resold between
       | datacenters, or migrated across regions. The Iranian filtering
       | system uses GeoIP databases and BGP information to decide which
       | IP ranges to trust and which to block. But those records lag
       | behind the changes.
       | 
       | This is surprising to me. Surely iranian ISPs would have directly
       | allocated IP space?
       | 
       | Or alternatively, surely Iran's gov would be in the routers and
       | be able to blackhole any routes leaving the country?
        
         | immibis wrote:
         | Are they sanctioned away from RIPE? Russia is. Russia isn't
         | allowed to be allocated any IP addresses they don't already
         | have. They're Russia, so they already have a bunch, but if they
         | didn't, they'd have to keep borrowing them on grey markets,
         | possibly different ones each time.
         | 
         | (Fun fact about sanctions: the International Criminal Court is
         | sanctioned away from Microsoft, so they can't legally get
         | access to Windows or Office. This is because they prosecuted a
         | war criminal the USA likes.)
        
       | elternal_love wrote:
       | If you are ever thinking of writing somethings like this: please
       | be aware that people could be executed based upon the validity of
       | your assumptions and advice offered.
        
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