Executive Summary
- Since June 18, Iran has experienced a near-complete internet blackout. June 21 marks the lowest point in host visibility, after which we see signs of recovery that continue as of this post.
- Return to connectivity has varied across different networks. Some, such as AS25124 (DATAK) and AS1756 (HAMYAR-AS), continue to experience significant instability. Others, such as AS42337 (RESPINA-AS) and AS50810 (MOBINNET-AS), have roared back to life.
- Telecommunication Infrastructure Company, or TIC, is observed as a transit path for almost every network that appears to be experiencing the slowest recovery.
- We’ve created a small dashboard of Iranian internet infrastructure as seen by Censys.
Introduction
Since around June 18th, 2025, Iran has been experiencing a near-complete internet blackout. This disruption has been independently confirmed by monitoring organizations such as @netblocks and IODA. We’ve also observed clear signs in our own scan data: our internal monitoring system, which tracks shifts in connection success and error rates across regions, detected a sudden and sustained spike in failures targeting Iranian IP space. In other words, services and hosts that used to be up and running were suddenly either timing out or getting a connection reset.
When plotting the total number of hosts observed in Censys data since June 16, 2025, we see a noticeable trend: around June 18, the host count begins to dip slightly, but by June 19, it drops sharply. This decline aligns closely with widespread reports and confirmation of a large-scale internet disruption in Iran.
June 21st appears to mark the lowest point in host visibility. After that, we began to see signs of recovery, with connectivity in Iran gradually returning. Our success/error rate monitoring reflected this shift as well, showing a significant rise in successful connections to Iranian hosts.
Autonomous Systems with Weak Recovery
However, not all is well in the country when it comes to internet connectivity. By examining the autonomous systems (ASNs) that experienced the highest number of hosts going offline during the outage window and comparing their host counts as of June 16th, 2025, we can identify several ASNs that, although some are showing signs of recovery, are still experiencing significant instability and limited restoration.
The bar graph below illustrates the number of hosts with connectivity at three points: the “Start” (shown in dark blue) represents the host count before the outage, the “Min” (orange) reflects the lowest point during the outage, and the “Recovered” (blue) indicates how many hosts came back online as connectivity was restored.
| ASN | Prev Count | Outage Count | Current | Recovery |
|---|---|---|---|---|
| AS25124 (DATAK) | 12870 | 1 | 4696 | 4695 |
| AS205647 (AFAGH) | 9325 | 1362 | 1362 | 0 |
| AS48944 (ASKHALIJFARSONLINE) | 6301 | 636 | 636 | 0 |
| AS202391 (AFRARASA-AS) | 6094 | 661 | 661 | 0 |
| AS208161 (PARSVDS) | 5790 | 1684 | 1684 | 0 |
| AS16322 (PARSONLINE) | 4465 | 322 | 322 | 0 |
| AS213807 (TEHRANSERVER) | 3679 | 705 | 705 | 0 |
| AS39074 (IR-SEPANTA) | 3461 | 119 | 1637 | 1518 |
| AS60976 (POL) | 3358 | 697 | 697 | 0 |
In the above table, we highlight the top ten ASNs that have either shown no recovery or only minimal recovery since the start of the outage. For instance, AS25124 (DATAK) once had over 12,000 observable hosts in Censys. By June 21st, all but one had gone offline. However, by June 23rd, that number had risen to around 4,695, indicating that some efforts to restore connectivity were underway.
A similar trend is visible with AS1756 (Shiraz Hamyar Co.), a telecommunications provider based in Iran. At its peak, Censys observed over 11,000 hosts. During the outage, that number plummeted to just 752. As of June 23rd, the host count has increased to approximately 4,500, indicating a slow but ongoing recovery.
A Common Thread
One critical piece of infrastructure ties all of these ASNs together: AS49666, the Telecommunication Infrastructure Company (TIC.IR), provides transit (internet connectivity) for every ISP in Iran. This means that if TIC experiences an outage, all downstream connectivity is affected. TIC is also owned and operated by the Government in Iran, and could likely be limiting internet access itself.
While the number of directly connected hosts in this ASN has historically been low, we’ve observed a notable increase in connected hosts as overall connectivity in Iran begins to recover. What this means exactly is not something we can answer, but it is an interesting insight nonetheless. Below is a host count graph for TIC itself.
Autonomous Systems with Strong Recovery
On the other hand, several ASNs not only recovered quickly but even surpassed their pre-outage host counts. This could suggest that, amid the disruption, some customers migrated to alternative ISPs. Alternatively, it may indicate that during the recovery process, previously unexposed hosts were inadvertently brought online. So not all has been bad news.
| ASN | Prev Count | Outage Count | Current | Recovery |
|---|---|---|---|---|
| AS42337 (RESPINA-AS) | 48785 | 24711 | 49219 | 24508 |
| AS50810 (MOBINNET-AS) | 45383 | 2 | 44967 | 44965 |
| AS49100 (IR-THR-PTE) | 17044 | 9521 | 17704 | 8183 |
| AS44208 (FARAHOOSH) | 10243 | 5018 | 10302 | 5284 |
| AS24631 (FANAPTELECOM) | 5456 | 2328 | 5756 | 3428 |
| AS34918 (PISHGAMAN) | 5081 | 2644 | 5424 | 2780 |
| AS59441 (HOSTIRAN) | 4546 | 3816 | 4980 | 1164 |
| AS48715 (SEFROYEKPARDAZENG) | 4002 | 1 | 4084 | 4083 |
| AS60077 (AT-CLOUD) | 3919 | 2554 | 5318 | 2764 |
| AS48147 (AMINIDC) | 3547 | 2621 | 3678 | 1057 |
For example, AS42337 (Respina Networks), a major telecom provider in Iran, lost more than half of its internet-connected hosts during the outage. Since then, it has made a strong recovery, with over a thousand additional hosts coming online in the past day. An even more dramatic rebound occurred with AS50810 (MOBINNET), a mobile network operator in Iran. During the outage, it dropped to just two observable hosts, but has now regained nearly all of its pre-outage visibility.
Largest Observed Host Count Drops
Finally, we can also look at the top 5 ASNs in Iran that had the largest drop in host count during this outage.
| ASN | Pre-Outage Hosts | Mid-Outage Hosts | Host Difference |
|---|---|---|---|
| AS206065 (FDI) | 85,969 | 28,181 | 57,788 |
| AS42337 (RESPINA-AS) | 48,785 | 24,711 | 24,074 |
| AS43754 (ASIATECH) | 29,115 | 16,688 | 12,427 |
| AS50810 (MOBINNET-AS) | 45,383 | 23,560 | 21,823 |
| AS58224 (TCI) | 356,555 | 109,841 | 246,714 |
Iran Connectivity Dashboard
To help the general public better understand the situation, we’ve created a public dashboard that presents key statistics on Iran’s internet connectivity from the perspective of Censys’s active scanning.
