Hello,

In collaboration with CAIDA/IODA and Iranian community members (Kandoo), we co-published a research report which shares measurement data and technical observations on Iran's internet blackout.

Our report is available here: https://ooni.org/post/2019-iran-internet-blackout/

Iran’s nation-wide Internet blackout is confirmed by several data sources, such as IODA, Google traffic data, and Oracle’s Internet Intelligence data. These data sources show that the Internet blackout in Iran started on 16th November 2019 and has been ongoing. As of 21st November 2019 (and more drastically from 23rd November 2019), Internet connectivity is being restored in Iran.

IODA data shows that Iranian cellular operators were disconnected first on 16th November 2019 (followed by almost all other operators over the next 5 hours), and that ISPs appear to have used diverse mechanisms to enforce the blackout.

By analyzing packet captures from the MCCI (AS197207) network, we found that a RST packet is injected at both ends of the connection.

During the blackout, most Iranians were barred from connecting to the global Internet, but they still had access to Iran’s national intranet: the domestic network hosting Iranian websites and services.

Yet, OONI measurements (which require Internet connectivity) were collected from multiple networks in Iran between 16th November 2019 to 23rd November 2019, showing that the internet blackout was not total.

To explore whether and how connectivity to the Internet could be possible from Iran during the blackout, we performed manual testing locally.

We found that DNS tunneling could possibly be a low bandwidth solution to get network traffic to leave Iran.

We also found that it was possible to connect to the Internet by using virtual private servers (VPS) to setup a local proxy in Iran and use that proxy to tunnel traffic to another proxy outside Iran.

Please share this report with your networks: https://twitter.com/OpenObservatory/status/1198321792076701696

Thank you,

~ OONI team.