Connectivity: A country going dark
Signal of the Twelve-Day War, June 2025
Iran ran a phased 'stealth blackout' that cut national connectivity to roughly 3% of normal, a 97% drop, deepening from the first Israeli strikes on 13 June to a near-total shutdown by 18 June. Unlike its 2019 brute-force cutoff, Iran kept its routes announced and its domestic intranet, banking and whitelisted apps online while severing real access to the global internet with DNS poisoning, protocol whitelisting and deep packet inspection. Independent outage monitors watched it happen in near-real-time.
Reading a blackout built from DNS poisoning and deep packet inspection is the kind of security work AI labs hire for too, and AITraining.jobs, our own database of AI-training work, lists the cybersecurity roles in which experts attack and audit AI systems.
Explore on the globeAttributes
- The question
- How, and how completely, did Iran cut its own population off from the internet, and who could still get through?
- Connectivity fell to about 3% of normal
- Georgia Tech's IODA measured Iranian internet usage collapsing to roughly 97% below normal at the peak of the shutdown around 18 June.
- A phased, deliberate escalation
- Disruptions began the morning of 13 June, deepened by 16 June, dropped sharply again on the evening of 17 June, and reached a near-total nationwide shutdown by about 12:50 UTC on 18 June.
- A 'stealth' blackout, not a plug pull
- Unlike 2019, Iran did not withdraw its BGP routes, so it still looked 'reachable' to routing monitors. Access was severed at the border with DNS poisoning, protocol whitelisting and deep packet inspection.
- The domestic intranet stayed up
- Iran's National Information Network kept government portals and internal platforms working, and the central bank said banking was 'functioning normally' even as foreign sites were unreachable.
- WhatsApp and Instagram blocked; VPN demand up 707%
- WhatsApp, Instagram and the app stores were blocked, with state TV urging Iranians to delete WhatsApp; VPN-related searches spiked about 707% as people tried to get around the wall.
Linked objects
signal of