Study: users in China's Henan province were on average denied access to 5x more websites than a typical Chinese internet user between Nov. 2023 and March 2025
once blocking 10× more domains than the GFW. 👉 https://gfw.report/... [image] @gfw_report : Henan Firewall now has an official Wikipedia page! Huge thanks to @Timfurry233 and many other dedicated volunteers! It's currently only in Chinese, so if you'd like to contribute, we'd love your help creating an English edition. https://zh.wikipedia.org/... [image] Marc Hofer / @marchofer : Interesting new paper by @gfw_report on the nature of provincial firewalls inside China, enclosed by the Great Firewall. To this date there is not much material on it but such research delivers valuable insights. [image] @hrichina : A new report by independent NGO Great Firewall Report documents an alarming sign of regional censorship in China: in Henan, its Firewall engages in volatile and aggressive blocking of second-level domains that far exceeds the national average. Read more: https://gfw.report/...
Context & Ripple Effects
The finding adds a provincial layer to coverage that has largely measured China’s national filtering system. Earlier GFWeb tracking of national domain blocklists showed how domain-level censorship can be observed at scale, while this study distinguishes Henan’s filtering footprint from that baseline.
It also reinforces that blocking is not a clean, uniform mechanism: prior university research found that the national system blocked many domains seemingly by accident, including in a 2020 measurement study of Great Firewall overblocking. Henan’s higher rate of second-level-domain blocking makes the local consequences of that approach more consequential.
First-order effects
- People connecting from Henan face a materially narrower reachable web than users elsewhere in China, with the study reporting five times as many denied websites on average over the measured period.
- Website operators and services whose domains or subdomains are caught by Henan’s filters can lose access to users in the province even when they remain reachable through the national baseline.
Second-order effects
- National-level measurements alone become less reliable proxies for the Chinese internet: researchers, platforms, and users must account for province-specific reachability when interpreting access data.
- More aggressive second-level-domain blocking can increase collateral disruption for services that share domain infrastructure, echoing the broader risk highlighted by research into accidental Great Firewall blocking.
Third-order effects
- If provincial filtering continues to diverge from the national system, China’s internet controls may function increasingly as a patchwork of regional access regimes rather than one uniform perimeter.
- The study strengthens the case for continuous, geographically distributed censorship measurement; without it, the practical scope of restrictions and their spillover effects can remain hidden.
The trend: This is one data point in the regionalization of internet controls, where subnational enforcement can impose access limits beyond a country’s headline national firewall.