Iran Internet Censorship: A Plain-English Overview
An overview of how internet censorship works in Iran — DNS blocking, DPI, protocol filtering, and the impact on information access.
Context
Iran operates one of the most extensive internet filtering systems in the world. Understanding how this system works is essential for researchers, journalists, and anyone studying digital rights in the region.
Safety note: This article describes censorship mechanisms for educational purposes. It does not provide operational circumvention instructions.
Key Filtering Techniques
DNS Filtering
Iranian ISPs redirect or block DNS queries for thousands of domains, including international news sites, social media platforms, and messaging services.
Deep Packet Inspection
Iran's filtering infrastructure uses DPI to identify and throttle or block specific protocols, including many VPN and proxy tools.
Protocol Blocking
Common VPN protocols are fingerprinted and blocked at the network level. This has driven research into more resilient approaches — the focus of IranVPN research.
Internet Shutdowns
During periods of unrest, authorities have implemented regional or national internet shutdowns, cutting off access entirely.
Impact on Information Access
Iranian users face significant challenges accessing independent news, educational resources, and communication tools. The impact extends to diaspora communities trying to communicate with family inside the country.
Our Research Approach
IranVPN documents these techniques through open research, prioritizing safety education over operational details. Read our censorship research hub for more.
Related Articles
Related pages
Related Articles
Open Signal Foundation 2026 Roadmap
Our 2026 roadmap: website launch, FreeWave demo, IranVPN research, security audits, and the path to NGO pilot deployment.
How Digital Safety Changes Under Censorship
Digital safety practices that matter more when internet censorship is active — risk assessment, privacy basics, and informed decision-making.
What Is a QR Broadcast?
QR broadcasts encode digital content into scannable video frames, enabling offline information distribution without internet connectivity.