Chinese-language Wikipedia views grew from 12.8 million per day in December 2019 to 13.9 million during the Wuhan lockdown (24 January–13 March) and peaked at 14.7 million per day from mid-February through April 2020; the crisis disproportionately increased views of pages selectively blocked by the Great Firewall prior to 2015, of historical Chinese leaders since Mao, and of current officials — categories expected only under a gateway effect — and these elevated levels persisted through May 2020.

The COVID-19 Wuhan lockdown caused geolocating Twitter users in China to increase 1.4-fold immediately, remaining 10% above pre-crisis baseline long-term; approximately 320,000 new Chinese users joined Twitter due to the crisis, and the available VPN application's ranking on the Chinese iPhone App Store jumped significantly around 23 January 2020 and maintained that elevated rank.

Crisis Increased Censorship Circumvention evaluation

In countries with no Great Firewall-equivalent censorship (Germany, Italy) and in less-censored authoritarian states (Iran — Persian Wikipedia; Russia — Russian Wikipedia) that experienced comparable COVID-19 outbreaks, no analogous spillover to politically sensitive content was observed; Wikipedia engagement in those countries increased generally but did not show disproportionate access to historically censored topics, confirming the gateway effect is specific to high-censorship environments.

Comparison with Other Countries Affected by the Crisis / Table 1 evaluation

Once mainland China users circumvented the Great Firewall during COVID-19, they disproportionately followed politically sensitive accounts: international news agencies at 1.31x the expected rate, Chinese citizen journalists at 1.42x, and political activists at 1.23x — all relative to Hong Kong users as a control — while state media accounts saw only a 1.06x increase and entertainment accounts a 0.85x decrease, confirming a selective gateway to censored political content.

Crisis Provided a Gateway to Censored Political Information / Types of Twitter accounts evaluation

Circumvention activity varied strongly by geographic proximity to the crisis: Hubei province, the epicenter, saw Twitter volume double relative to pre-lockdown baseline and sustain that doubling 30 days after the crisis, while mobility decreases from Baidu location data correlated with Twitter user increases across provinces — but two weeks after lockdown, the elevated Twitter usage could no longer be explained by mobility restrictions or New Year seasonality, indicating crisis-induced circumvention becomes self-sustaining.

Increases in Circumvention Occurred throughout China / Fig. 4 evaluation

Article 19 documents that Iran's National Information Network (NIN / SHOMA) was designed with explicit reference to China's Great Firewall as a model, with institutional mirroring: Iran's Supreme Council of Cyberspace parallels China's Cyberspace Administration of China, and both governments share a "cyber sovereignty" doctrine used to justify domestic content controls and cross-border technology transfer. The report frames Iran's filtering infrastructure as deliberately architected to replicate GFW capabilities, not as an independently developed system.

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DNS censorship of encrypted protocols is inconsistent in both China and Iran. In China, Yandex resolvers are censored only when the SNI extension is present; omitting SNI bypasses censorship for these resolvers. In Iran, DoH requires SNI omission for Quad9, Google, Adguard, CleanBrowsing, and NextDNS resolvers, but works with SNI for Yandex and Cisco resolvers. These inconsistencies suggest resolvers have been accidentally missed by censors, highlighting the value of automated tools that trial all resolver-mode combinations rather than hard-coding a single strategy. The support evaluation found 47 resolvers supporting DoH, 16 supporting DoH3, and only 8 supporting DoQ out of ~65 tested.

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DPYProxy-DNS tested 8 circumvention modes against DNS censorship from vantage points in Iran (AS201295, Mashhad) and China (AS4837, China Unicom). In Iran, DoQ was entirely uncensored even with the SNI extension present; DoH3 worked for all Cloudflare and NextDNS resolvers. Iran's censor operates in-path (not on-path like the GFW), making the "Last Response" mode (wait 3s for the last UDP reply) ineffective in Iran but highly effective in China. Auto-mode averaged 12.32s (median 8.28s) in Iran and 13.78s (median 12.90s) in China to discover a working combination.

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DPYProxy-DNS's automated probe-and-select mode identified a working DNS circumvention in an average of 13.78 seconds (median 12.90s) in China and 12.32 seconds (median 8.28s) in Iran across 100 runs each; best-case startup was 0.32s (China) and 0.47s (Iran) when the first-tried combination succeeded, while worst-case exceeded 30.72s in China and 58.16s in Iran due to the slow Last Response mode (3s fixed wait per attempt) being selected early in the randomized probe order.

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Pakistan's PECA (Prevention of Electronic Crimes Act) and PTA (Pakistan Telecommunication Authority) regulations grant authority to block content without court orders, enabling the deployment of a persistent national filtering infrastructure. The report documents 11,000+ URLs blocked by PTA and confirms that VPN use and circumvention tools are among the targeted categories, with blocking orders issued under national security grounds.

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GFWeb tested 1.02 billion domains against the GFW over 20 months and discovered 943,000 pay-level domains blocked by HTTP filters and 55,000 by HTTPS filters — the largest GFW blocklist dataset ever published. The HTTP-to-HTTPS ratio (17:1) confirms that the GFW's HTTPS keyword-based and SNI-based blocking covers far fewer domains than its HTTP host-header blocking, likely because HTTPS blocks carry higher collateral-damage risk.

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