voidly
Active Incident

Confirmed: great Firewall baseline

China · January 1, 2017 · 3651 days

OONI detected censorship pattern in China. Great Firewall baseline. Anomaly rate: 100.0%

Evidence

100%
Anomaly Rate
24,231,942
Measurements
95%
Confidence

What This Means

100% of 24,231,942 network tests from China failed to reach these services. Global baseline failure rate is typically 1-3%. This 97+ percentage point difference strongly indicates intentional blocking.

How We Detected This

Data Sourceooni + censoredplanet
ML ModelGradientBoosting v3.3 (LOCO median F1 0.87, honest across 127 countries)
Confidence Score95% certainty of censorship
Detection TimeJanuary 1, 2017

Corroborating Evidence (11211)

Evidence collected from multiple independent sources. Upstream claims shown in quotes are not Voidly assertions.

OONIOpen Observatory of Network Interference8975 records
interference
"OONI web_connectivity: 162/406 measurements anomalous (39.9%)"OONI report
Signal value: 0.40
Aug 4, 2026
View source →
blocking
"OONI signal: 3/4 measurements anomalous (75.0%)"OONI report
Signal value: 0.75
Aug 4, 2026
View source →
blocking
"OONI whatsapp: 3/4 measurements anomalous (75.0%)"OONI report
Signal value: 0.75
Aug 4, 2026
View source →
blocking
"OONI telegram: 3/4 measurements anomalous (75.0%)"OONI report
Signal value: 0.75
Aug 4, 2026
View source →
blocking
"OONI facebook_messenger: 3/4 measurements anomalous (75.0%)"OONI report
Signal value: 0.75
Aug 4, 2026
View source →
+ 8970 more OONI records
Censored PlanetUniversity of Michigan research2236 records
http-blocking-tcp-reset
"HTTP blocking (tcp-reset): 47/60 probes blocked (78.3%) for getlantern.org"Censored Planet report
Signal value: 0.78
Aug 3, 2026
View source →
http-blocking-tcp-reset
"HTTP blocking (tcp-reset): 47/60 probes blocked (78.3%) for huggingface.co"Censored Planet report
Signal value: 0.78
Aug 3, 2026
View source →
http-blocking-tcp-reset
"HTTP blocking (tcp-reset): 44/60 probes blocked (73.3%) for instagram.com"Censored Planet report
Signal value: 0.73
Aug 3, 2026
View source →
http-blocking-tcp-reset
"HTTP blocking (tcp-reset): 46/60 probes blocked (76.7%) for medium.com"Censored Planet report
Signal value: 0.77
Aug 3, 2026
View source →
http-blocking-tcp-reset
"HTTP blocking (tcp-reset): 44/60 probes blocked (73.3%) for nytimes.com"Censored Planet report
Signal value: 0.73
Aug 3, 2026
View source →
+ 2231 more Censored Planet records

Affected Services (25)

Amnesty InternationalBBCChatGPTClaudeClubhouseDeutsche WelleDiscordFacebookFacebook MessengerGeminiHuman Rights WatchInstagramLanternMediumNew York TimesProton VPNProtonVPNPsiphonSignalTelegramThe GuardianTikTokTorTwitchTwitter/X

Blocked Domains (25)

What we cannot say

  • Who caused it — measurement data alone does not attribute this to any government, ISP, or other actor.
  • Intent — anomalous or unreachable measurements indicate interference, not a stated motive or a deliberate-vs-incidental determination.
  • Which networks — no specific ASN/ISP is identified for this incident.
  • The mechanism — we cannot state whether this was DNS tampering, TLS/SNI reset, an HTTP blockpage, throttling, or an infrastructure outage.
  • Sub-national scope — measurement is aggregated at the country level; we cannot localize to a province, city, or network segment.

Cite This Incident

Voidly Research. (2017). Confirmed: great Firewall baseline [CN-2017-0001]. Voidly Global Censorship Index. https://voidly.ai/incident/CN-2017-0001

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