Users
We estimate the number of users by analyzing the requests induced by clients to relays and bridges.
This graph shows the estimated number of clients connecting via bridges. These numbers are derived from directory requests counted on bridges. Bridges resolve client IP addresses of incoming directory requests to country codes, and they distinguish connecting clients by transport protocol, which may include pluggable transports. Even though bridges don't report a combination of clients by country and transport, it's possible to derive and graph lower and upper bounds from existing usage statistics. For further details check the documentation on Reproducible Metrics.
Related events
The following events have been manually collected in the metrics-timeline Git repository and might be related to the displayed graph.
| Dates | Places/Protocols | Description and Links |
|---|---|---|
| 2026-03-09 | snowflake |
Update snowflake-01 bridge to tor 0.4.9.5
|
| 2026-03-05 | snowflake |
Update snowflake-02 bridge to tor 0.4.9.5 for a metrics issue.
issue issue |
| 2026-02-28 to present | Iran |
Internet shutdown in Iran.
comment BBS thread |
| 2026-02-10 | snowflake |
Update snowflake-01 bridge to tor 0.4.8.22 for a metrics issue.
issue |
| 2026-01-28 |
Release of tor 0.4.8.22. Includes a change to count consensus downloads only after they have completed. Before this, incomplete consensus downloads (such as could be caused by the blocking of Tor) would inflate apparent user count statistics.
announcement release notes issue |
|
| 2026-01-13 to 2026-01-17 | Uganda |
Internet shutdown in Uganda during general election.
issue OONI findings |
| 2026-01-08 to 2026-01-27 | Iran |
Internet shutdown in Iran.
issue BBS thread IODA graph |
| 2025-12-21 | snowflake |
Planned maintenance on the snowflake-01 server for verification of boot media \#3.
issue |
| 2025-12-21 | snowflake |
Planned maintenance on the snowflake-01 server for verification of boot media \#2.
issue |
| 2025-12-12 | snowflake |
Planned maintenance on the snowflake-01 server for verification of boot media \#1.
issue |
| 2025-12-12 | snowflake |
Planned maintenance on the snowflake-01 server for failing disk (again).
issue |
| 2025-11-21 | snowflake |
Planned maintenance on the snowflake-01 server for failing disk.
issue |
| 2025-09-20 to 2025-09-21 | Bridges snowflake website |
DNSSEC outage preventing resolution of torproject.org and torproject.net domains. This affects snowflake as well as the Tor Project website and some bridge distribution channels.
issue |
| 2025-08-20 | snowflake |
The Snowflake broker starts zeroing out the count of daily unique proxy IP addresses. Before this, only *new* proxy IP addresses (new since the last broker restart) had contributed to the count each day.
issue |
| 2025-08-20 | snowflake |
The Snowflake broker starts doing client IP address geolocation for ampcache rendezvous.
issue |
| 2025-08-02 to 2025-08-13 | snowflake |
Outage of the snowflake-02 bridge, caused by a hardware failure.
issue |
| 2025-06-26 to 2025-07-04 | Togo obfs4 vanilla |
Partial blocking of Tor directory authorities and default obfs4 bridges in Togo during protests.
issue |
| 2025-06-18 to 2025-06-21 | Iran |
Network shutdown in Iran.
effects on Snowflake BBS thread NTC thread |
| 2025-06-10 | conjure meek moat snowflake |
Temporary outage of CDN77 domain fronting.
issue |
| 2025-06-05 | Belarus webtunnel |
Removed WebTunnel from Connection Assist in Belarus.
merge request |
| 2025-06-05 | China webtunnel |
WebTunnel becomes the primary transport in Connection Assist in China.
merge request |
| 2025-06-05 | Myanmar webtunnel |
WebTunnel becomes the primary transport in Connection Assist in Myanmar.
merge request |
| 2025-06-05 | Turkmenistan meek obfs4 snowflake |
Snowflake becomes the primary transport in Connection Assist in Turkmenistan.
merge request fix commit |
| 2025-04-28 | Turkmenistan snowflake Unknown |
Sustained large increase in bridge users from Turkmenistan, especially Snowflake, from near zero to over 5,000.
comment bridge users graph anti-censorship team meeting discussion April 2025 Snowflake Daily Operations update |
| 2025-01-25 | Belarus |
Presidential election in Belarus.
relay graph bridge graph |
| 2024-12-16 to 2024-12-20 | snowflake |
The snowflake-broker.azureedge.net CDN configuration is non-functional, as part of the transition to a new broker.
comment graph |
| 2024-11-25 | Russia snowflake |
Migration of the Snowflake broker to a new host at a different IP address. Standalone proxies erroneously continue to poll the old broker. NAT behavior self-testing is briefly disrupted.
issue DNS change issue tor-relays post |
| 2024-11-06 to 2024-11-21 | Russia snowflake |
Blocking of Snowflake DTLS connections in Russia.
issue BBS thread NTC thread |
| 2024-09-30 | snowflake |
Redeployed the Snowflake probetest with another fix to NAT type testing, aimed at reducing the number of instances of "restricted".
issue |
| 2024-09-18 | Bridges |
Bridge distribution transitions from BridgeDB to rdsys.
comment mailing list post |
| 2024-09-10 | snowflake |
Redeployed the Snowflake probetest with fixes to NAT type testing, aimed at reducing the number of instances of "unknown".
issue |
| 2024-08-22 to 2024-08-23 | snowflake |
Outage of the Snowflake broker.
issue |
| 2024-06-18 | snowflake |
Release of version 0.8.3 of the Snowflake proxy WebExtension, hoped to restore proxy capacity with its fixed consent prompt.
comment graph |
| 2024-06-10 | Bridges |
The bridge authority upgrades to tor version 0.4.8.12 and begins rejecting bridges running version 0.4.7.
mailing list post |
| 2024-06-09 to 2024-06-13 | Algeria |
Shutdowns during university exams in Algeria.
issue blog post |
| 2024-05-30 to present | Myanmar |
Blocking of VPNs in Myanmar. Bridge users increase.
issue |
| 2024-05-14 to present |
High load leading to network performance issues.
status.torproject.org forum post |
|
| 2024-05-11 | snowflake |
Loss of about 60,000 WebExtension Snowflake proxies, after the release of version 0.8.2 of the proxy WebExtension, the first release available for Chrome adding a consent prompt that existing users didn't notice.
issue |
| 2024-05-02 |
Release of Orbot for Android 17.2.1-RC-2-tor-0.4.8.7, the first release of Orbot 17 to appear on the Google Play Store. Orbot Snowflake proxies (kindness mode) increase.
release graph of Snowflake proxies |
|
| 2024-04-08 | snowflake |
Loss of about 15,000 WebExtension Snowflake proxies, after the release of version 0.8.0 of the proxy WebExtension, which adds a consent prompt that existing users didn't notice. Version 0.8.0 was released only for Firefox, not for Chrome.
issue |
| 2024-03-29 to 2024-04-24 | snowflake Unknown |
Temporary reductions in users of the snowflake-01 bridge, with simultaneous increases in users of the snowflake-02 bridge.
issue forum post |
| 2024-03-16 to 2024-04-08 | snowflake |
Version 0.7.3 of the Snowflake WebExtension is removed from the Firefox Add-ons store because of a policy change. Version 0.8.0 adds a consent prompt and is re-added to the store.
issue |
| 2024-03-15 | snowflake Unknown |
The Snowflake bridges suddenly recover a large amount of bandwidth, two weeks after the Fastly domain fronting change of 2023-03-01.
mailing list post |
| 2024-03-06 | moat snowflake |
Release of Tor Browser 13.0.11, with workaround for the domain fronting change of 2024-03-01.
blog post Snowflake merge request Moat merge request |
| 2024-03-01 | moat snowflake |
Fastly stops supporting domain fronting. This affects Snowflake, Moat, and Connection Assist.
issue pre-announcement in November 2023 forum post bandwidth graphs |
| 2024-02-17 | snowflake |
Restart of snowflake-01 bridge for system upgrade
comment |
| 2024-02-17 | snowflake |
Restart of snowflake-01 bridge in preparation for upgrades
comment |
| 2024-02-09 |
Release of Orbot for Android 17.2.1-RC-1-tor-0.4.8.7.
release |
|
| 2024-02-08 to present | Pakistan |
Shutdowns on mobile ISPs in Pakistan on Election Day.
Cloudflare Radar tweet |
| 2024-02-04 to 2024-02-07 | Senegal |
Shutdown of mobile services in Senegal during protests.
article |
| 2024-01-31 to 2024-02-02 | Russia OR |
Plain Tor is temporarily unblocked in Russia.
NTC thread OONI chart |
| 2024-01-22 | snowflake |
Restart of snowflake-01 bridge for configuration and kernel updates
comment |
| 2023-12-21 | Bridges |
Release of Tor Browser 13.0.8. Fixes the problem of pluggable transports not running on Windows 7 and Windows 8, except for Snowflake.
blog post issue merge request |
| 2023-12-19 | Bridges |
Release of Tor Browser 13.0.7. Pluggable transports don't work with Windows 7 and Windows 8.
blog post issue |
| 2023-12-17 | snowflake |
Restart of snowflake-01 bridge for test of configuration changes
|
| 2023-12-15 | snowflake |
Upgraded tor from 0.4.8.8 to 0.4.8.10 on the snowflake-01 bridge. Fixes the bug that made user counts by country more imprecise.
comment graph monthly update |
| 2023-12-15 | snowflake |
Upgraded tor from 0.4.8.8 to 0.4.8.10 on the snowflake-02 bridge. Fixes the bug that made user counts by country more imprecise.
comment |
| 2023-12-08 |
Release of tor 0.4.8.10. Fixes TROVE-2023-007 affecting exit relays with Conflux. Fixes the bug that caused incorrect counting of pluggable transport users.
announcement |
|
| 2023-11-21 | snowflake |
Restarted the snowflake-02 bridge for a performance enhancement.
comment |
| 2023-11-21 | snowflake |
Restarted the snowflake-01 bridge for a performance enhancement.
comment |
| 2023-11-16 | Relays |
Removal of about 1,000 "ATOR" relays.
blog post blog post graph |
| 2023-11-07 | snowflake |
Restarted the snowflake-02 bridge for a performance enhancement. Upgraded tor from 0.4.8.6 to 0.4.8.8.
comment |
| 2023-10-20 | snowflake |
Restart of snowflake-01 bridge for Debian 11.8 upgrade. Upgraded tor from 0.4.8.6 to 0.4.8.7.
comment |
| 2023-10-12 |
Release of Tor Browser 13.0. First stable release with Conflux.
blog post tor-relays post |
|
| 2023-10-05 | snowflake |
Release of Orbot 17.1.0-RC-2-tor.0.4.7.14, again changing the domain front to attempt to work around Snowflake connection problems.
release commit |
| 2023-10-04 | snowflake Unknown |
The snowflake-02 bridge suddenly recovers a large amount of bandwidth, after two weeks of low usage following the domain front change of 2023-09-20.
mailing list post |
| 2023-10-03 | snowflake |
Upgraded tor from 0.4.7.13 to 0.4.8.6 on the snowflake-01 bridge. As with the upgrade on snowflake-02 on 2023-09-24, this causes the reporting of spurious OR protocol users.
comment mailing list post comment monthly update |
| 2023-09-28 | snowflake |
Release of Orbot 17.1.0-RC-1-tor.0.4.7.14, with an alternative domain front to attempt to work around Snowflake connection problems.
release commit |
| 2023-09-26 | snowflake |
Release of Tor Browser 12.5.5, with an alternative domain front to attempt to work around Snowflake connection problems.
blog post merge request |
| 2023-09-24 | snowflake |
Upgraded tor from 0.4.7.13 to 0.4.8.6 on the snowflake-02 bridge. As the result of an apparent bug, the bridge starts reporting a number of OR protocol users about equal to the number of Snowflake users.
mailing list post about upgrade mailing list post about metrics problems core Tor issue metrics issue |
| 2023-09-24 | snowflake |
Release of Tor Browser 13.0a5, with an alternative domain front to attempt to work around Snowflake connection problems.
blog post merge request |
| 2023-09-21 | snowflake Unknown |
The snowflake-01 bridge suddenly recovers a large amount of bandwidth, about 24 hours after the domain front change of 2023-09-20 started to lower the number of users.
mailing list post |
| 2023-09-20 | moat snowflake |
The front domain used by Snowflake, Moat, and Connection Assist starts sometimes resolving to a different CDN, which makes these services stop working for some users. The snowflake-01 bridge drops to about half its normal number of users; the snowflake-02 bridge drops almost to zero. There would later be sudden partial recoveries of usage on snowflake-01 at 2023-09-21 13:10:00 and snowflake-02 at 2023-10-04 11:40:00.
forum post about Snowflake forum post about Moat and Connection Assist |
| 2023-09-19 to 2023-10-31 | Azerbaijan |
Blocking of TikTok in Azerbaijan.
tweet about start tweet about end |
| 2023-09-19 to 2023-09-25 | Azerbaijan |
Blocking of Google Play Store in Azerbaijan.
tweet |
| 2023-09-04 to 2023-09-09 | United States Relays Unknown |
Unexplained spike in relay users from the US.
issue |
| 2023-08-27 to 2023-08-30 | snowflake |
Outage of the snowflake-02 bridge caused by a temporary network disconnection at the network host. Client polls at the broker increase and traffic is diverted to snowflake-01.
mailing list post article status page |
| 2023-08-23 to 2023-12-08 | Bridges |
A bug in tor 0.4.8.4 causes misattribution of about half of pluggable transport users to the plain Tor protocol in bridges that upgrade to this version. The bug is fixed in tor 0.4.8.10.
issue issue merge request |
| 2023-08-23 |
Release of tor 0.4.8.4, with new Conflux and anti-DoS proof-of-work features.
announcement |
|
| 2023-08-08 to present | Jordan |
Blocking of Grindr in Jordan.
OONI report |
| 2023-08-05 to present | Iraq |
Blocking of Telegram in Iraq.
Kentik report |
| 2023-08-03 | Turkmenistan meek snowflake |
Make meek the first choice in Connection Assist for Turkmenistan, and changed the meek front domain.
merge request |
| 2023-07-18 | Turkmenistan OR |
Blocking of the default Tor client TLS fingerprint in the AGTS ISP in Turkmenistan.
comment relay users graph |
| 2023-07-18 | snowflake |
Restarted snowflake-server on the snowflake-02 bridge with num-turbotunnel=8.
comment |
| 2023-07-18 | snowflake |
Restarted snowflake-server on the snowflake-01 bridge with num-turbotunnel=8.
comment |
| 2023-07-18 | snowflake |
Restarted snowflake-server on the snowflake-01 bridge with num-turbotunnel=1.
comment |
| 2023-07-01 | snowflake |
Restarted snowflake-01 bridge after testing performance optimizations.
comment |
| 2023-06-30 |
The number of allowed relays per IP address (AuthDirMaxServersPerAddr) is increased from 2 to 8.
announcement issue |
|
| 2023-06-29 | snowflake |
Restarted snowflake-01 bridge to test an optimization.
comment |
| 2023-06-29 | snowflake |
Restarted snowflake-01 bridge to test an optimization.
comment |
| 2023-06-29 | webtunnel |
Announcement of WebTunnel availability.
announcement |
| 2023-06-29 | snowflake |
Restarted snowflake-01 bridge to test an optimization.
comment |
| 2023-06-28 | snowflake |
Restarted snowflake-01 bridge for a profiling change.
comment |
| 2023-06-12 to 2024-05-06 | Germany Relays Unknown |
Increase in relay users from Germany.
issue graph forum thread |
| 2023-06-05 to 2023-06-07 | Senegal |
Blocking of mobile Internet in Senegal.
article |
| 2023-06-01 | conjure |
Announcement of Conjure availability.
announcement BBS thread |
| 2023-06-01 to present | Senegal |
Blocking of social media in Senegal.
article OONI report |
| 2023-05-31 | snowflake |
Release of Orbot 17.1.0-BETA-2-tor.0.4.7.11.
release |
| 2023-05-22 | snowflake |
Restarted the snowflake-01 bridge for an upgrade.
comment |
| 2023-05-21 | snowflake |
Restarted the snowflake-02 bridge for an upgrade.
comment |
| 2023-05-12 to 2023-05-14 | China snowflake |
Block of Snowflake default front domain in China.
issue BBS thread forum thread |
| 2023-04-26 to present | Brazil |
Block of Telegram in Brazil.
OONI report |
| 2023-04-23 to 2023-04-25 | Sudan |
Internet outage in Sudan.
liveblog Wikipedia |
| 2023-04-19 | China obfs4 snowflake |
Changed the recommended transport in Connection Assist in China from obfs4 to snowflake.
comment commit |
| 2023-04-12 | snowflake |
Orbot begins a release rollout of version 17.0.0-RC-1-tor.0.4.7.11. First release of Orbot to include the snowflake-02 bridge along with the existing snowflake-01. Has a change to the Snowflake DTLS fingerprint (removes Hello Verify Request) to mitigate reported blocking in Russia.
release Orbot commit adding snowflake-02 IPtProxy commit upgrading Snowflake |
| 2023-04-11 | snowflake |
Release of Snowflake WebExtension 0.7.2, with a fix for missing client country information that had been introduced in 0.6.0 on 2022-06-27. The result is better country-level attribution of Snowflake users: most who had been being assigned to ?? are now assigned to their proper geolocated country.
archive comment |
| 2023-04-11 | China obfs4 Unknown |
Sudden drop in access to bridges from the "settings" and "moat" pools from China.
comment bridge graph |
| 2023-04-08 | snowflake |
Deployed a performance optimization on the snowflake-01 bridge.
comment |
| 2023-04-07 | snowflake |
Deployed a performance optimization on the snowflake-02 bridge.
comment |
| 2023-03-31 to 2023-04-18 | webstats Unknown |
Tor Browser update pings temporarily drop further.
graph issue |
| 2023-03-22 | snowflake |
Rebooted the snowflake-02 bridge to make nf_conntrack changes persistent.
comment |
| 2023-03-22 | webtunnel |
Release of Tor Browser 12.5a4, first release with WebTunnel for mobile.
blog post issue |
| 2023-03-22 | snowflake |
Rebooted the snowflake-01 bridge to make nf_conntrack changes persistent.
comment |
| 2023-03-19 | Iran moat snowflake |
The domain name cdn.sstatic.net, which is used by Snowflake and Moat, is again blocked in some ISPs in Iran.
comment OONI chart |
| 2023-03-15 | snowflake |
Release of Orbot for Android v17 BETA 2. First release of Orbot to include the snowflake-02 bridge along with the existing snowflake-01. Has a change to the Snowflake DTLS fingerprint (removes Hello Verify Request) to mitigate reported blocking in Russia.
release Orbot commit adding snowflake-02 IPtProxy commit upgrading Snowflake |
| 2023-03-13 | snowflake |
Restarted snowflake-01 bridge for a bugfix.
comment issue |
| 2023-03-13 | snowflake |
Restarted snowflake-02 bridge for a bugfix.
comment issue |
| 2023-03-13 | Iran moat snowflake |
The domain name cdn.sstatic.net, which is used by Snowflake and Moat, is again blocked in some ISPs in Iran.
comment OONI chart |
| 2023-03-10 to 2023-03-13 | snowflake |
Temporarily restarted snowflake-server on the snowflake-02 bridge to activate the Go race detector.
comment |
| 2023-03-10 | United Arab Emirates obfs4 snowflake |
Removed Connection Assist settings for the United Arab Emirates.
merge request |
| 2023-03-08 | Iran moat snowflake |
The domain name cdn.sstatic.net, which is used by Snowflake and Moat, is again blocked in some ISPs in Iran.
comment OONI chart |
| 2023-03-06 | snowflake |
Re-increased firewall connection tracking limits on the snowflake-01 and snowflake-02 bridges, which had been unintentionally reduced to the defaults since 2023-02-16.
comment |
| 2023-03-03 | Iran moat snowflake |
The domain name cdn.sstatic.net, which is used by Snowflake and Moat, is again blocked in some ISPs in Iran.
comment OONI chart |
| 2023-02-22 | Iran moat snowflake |
The domain name cdn.sstatic.net, which is used by Snowflake and Moat, is again blocked in some ISPs in Iran.
comment OONI chart |
| 2023-02-20 | conjure |
Release of Tor Browser 12.5a3, first release with Conjure.
blog post issue |
| 2023-02-19 | Iran moat snowflake |
The domain name cdn.sstatic.net, which is used by Snowflake and Moat, is again blocked in some ISPs in Iran.
comment OONI chart |
| 2023-02-17 | snowflake |
Restarted snowflake-01 bridge for HAProxy security update.
comment |
| 2023-02-16 | snowflake |
Increased the number of tor instances on the snowflake-02 bridge from 4 to 12.
issue |
| 2023-02-16 | snowflake |
Restarted snowflake-02 bridge for HAProxy security update.
comment |
| 2023-02-15 | snowflake |
Release of Tor Browser 12.0.3. Has a change to the Snowflake DTLS fingerprint (removes Hello Verify Request) to mitigate reported blocking in Russia.
blog post comment about Hello Verify Request Snowflake merge request Tor Browser merge request |
| 2023-02-10 to 2023-02-13 | Iran moat snowflake |
The domain name cdn.sstatic.net, which is used by Snowflake and Moat, is again blocked in some ISPs in Iran.
comment OONI chart |
| 2023-02-09 to present | Ethiopia |
Social media blocking in Ethiopia.
relay graph bridge graph BBS thread |
| 2023-02-01 to present | Senegal |
Blocking of TikTok in Senegal.
tweet |
| 2023-01-31 to 2023-02-01 | Iran moat snowflake |
The domain name cdn.sstatic.net, which is used by Snowflake and Moat, is again blocked in some ISPs in Iran.
comment |
| 2023-01-20 to present | webstats Unknown |
Tor Browser update pings drop temporarily. A similar effect is present in other years.
graph issue |
| 2023-01-19 | Iran |
Shutdown in some ISPs in Iran during student exams.
Cloudflare Radar |
| 2023-01-16 to 2023-01-24 | Iran moat snowflake |
The domain name cdn.sstatic.net, which is used by Snowflake and Moat, is blocked in some ISPs in Iran.
comment |
| 2023-01-12 | ipv4 ipv6 |
geoip and geoip6 databases updated to "IPFire Project Thu, 12 Jan 2023 05:25:41 GMT" (geoip-db-digest D48EC82E3F03A0C929B6D85FBA12D538524AC9B1, geoip6-db-digest BB4E522D86A3C1FB6E820A69F4AA16DAC953B05B).
commit |
| 2023-01-12 | snowflake |
Restarted snowflake-server on the snowflake-01 bridge with num-turbotunnel=4.
issue |
| 2023-01-05 | China obfs4 Unknown |
Sudden drop in access to bridges from the "email" pool from China.
comment bridge graph |
| 2022-12-21 | webtunnel |
Release of Tor Browser 12.5a1, first release with WebTunnel for desktop.
blog post merge request |
| 2022-12-20 | snowflake |
Increased firewall connection tracking limits on the snowflake-02 bridge.
issue |
| 2022-12-15 | Russia obfs4 snowflake |
Made obfs4 preferred over Snowflake in Connection Assist for Russia.
merge request |
| 2022-12-13 | snowflake |
Increased firewall connection tracking limits on the snowflake-01 bridge.
comment |
| 2022-12-07 | snowflake |
Release of Tor Browser 12.0, the first stable release to contain both the snowflake-01 and snowflake-02 bridges.
issue blog post BBS comment NTC comment |
| 2022-12-06 | ipv4 ipv6 |
geoip and geoip6 databases updated to "IPFire Project Thu, 10 Nov 2022 06:23:12 GMT" (geoip-db-digest A5C34FC3C709B524ADE33779FFD75C64D1F5003D, geoip6-db-digest 10AAC07E3C77361DF777A0DC1EA956997CB8D439).
commit |
| 2022-12-06 | ipv4 ipv6 |
geoip and geoip6 databases updated to "IPFire Project Sun, 04 Dec 2022 05:55:29 GMT" (geoip-db-digest 7F3C80C728C56ABA89C3E56279BECFD39314DD97, geoip6-db-digest FD15242DA08323FC66363B431359313374633FDC).
commit |
| 2022-12-01 | snowflake |
Release of Tor Browser 12.0a5, the first release to contain both the snowflake-01 and snowflake-02 bridges.
issue announcement BBS comment |
| 2022-11-18 | Russia meek |
Reported blocking of the meek-azure front domain in Russia.
NTC post |
| 2022-11-15 | United Arab Emirates obfs4 snowflake |
Added obfs4 and Snowflake settings to Connection Assist for the United Arab Emirates.
merge request |
| 2022-11-10 |
Release of tor 0.4.7.11, with mitigations against network denial of service.
announcement |
|
| 2022-11-01 | Iran snowflake |
Orbot begins a gradual release rollout of version 16.6.3-RC-1-tor.0.4.7.10, which has TLS fingerprint changes to make Snowflake work in Iran again.
release |
| 2022-10-27 | snowflake |
Release of Tor Browser 11.5.6. Fixes the problem that prevented Snowflake from working in 11.5.5, and enables uTLS TLS camouflage support by default for Snowflake.
blog post issue |
| 2022-10-26 | snowflake |
Distributed snowflake-01 outgoing traffic over five IP addresses, in an attempt to mitigate anti-DDoS false detections by other relays.
comment |
| 2022-10-26 | snowflake |
Reboot of the snowflake-01 bridge for software updates.
|
| 2022-10-25 | meek snowflake |
Release of Tor Browser 11.5.5. Adds a new working default meek bridge. Intended to enable uTLS TLS camouflage support by default for Snowflake, but had a bug that prevented Snowflake from working.
blog post issue |
| 2022-10-20 | snowflake |
Release of Orbot for Android 16.6.3-BETA-2-tor.0.4.7.10. Adds uTLS TLS camouflage support for Snowflake, making it possible to circumvent recent TLS blocking in Iran.
release announcement |
| 2022-10-19 | snowflake |
Reboot of the snowflake-01 bridge for software updates.
|
| 2022-10-17 | Iran snowflake |
Changed the uTLS fingerprint from hellochrome_auto to hellorandomizedalpn for Snowflake in Iran in Connection Assist, and reverted an inadvertent broker domain front change.
comment |
| 2022-10-17 | Iran snowflake |
Enabled uTLS for Snowflake in Iran in Connection Assist, using the hellochrome_auto fingerprint.
comment merge request |
| 2022-10-17 to 2022-10-25 | snowflake |
Temporary experiment with reverting the 2022-10-03 Snowflake broker change to require multi-bridge support in proxies.
comment for beginning comment for end meeting notes meeting log |
| 2022-10-17 | China Hong Kong obfs4 snowflake |
Changed the recommended transport in Connection Assist to obfs4 in China (was snowflake) and Hong Kong (was unspecified).
issue merge request meeting notes |
| 2022-10-12 | snowflake |
Release of Tor Browser 11.5.4. Adds uTLS TLS camouflage support for Snowflake, making a manual configuration possible to circumvent recent TLS blocking in Iran.
blog post BBS comment |
| 2022-10-05 to 2022-12-05 | meek |
The default meek-azure bridge meek has a configuration issue and the metrics website cannot process statistics.
issue |
| 2022-10-04 | snowflake |
Snowflake rendezvous blocked by TLS fingerprint in Iran.
issue BBS thread |
| 2022-10-04 | meek |
The default meek-azure bridge cymrubridge02 goes offline.
issue |
| 2022-10-03 | snowflake |
Outage of the snowflake-01 bridge caused by a change in firewall rules.
comment |
| 2022-10-03 | snowflake |
Deployment of Snowflake broker to reject proxies that do not support multiple bridges.
issue issue |
| 2022-10-02 | snowflake |
Mitigation of ephemeral port exhaustion on the snowflake-01 bridge.
comment |
| 2022-10-02 | snowflake |
Partial mitigation of ephemeral port exhaustion on the snowflake-01 bridge.
comment |
| 2022-10-02 | snowflake |
Attempted mitigation of ephemeral port exhaustion on the snowflake-01 bridge.
comment |
| 2022-10-02 | snowflake |
Attempted mitigation of ephemeral port exhaustion on the snowflake-01 bridge.
comment |
| 2022-10-02 | snowflake |
Restart of snowflake-server on the snowflake-01 bridge, multiple KCP instances.
comment |
| 2022-10-01 | snowflake |
Restart of snowflake-server on the snowflake-01 bridge, with a reduction in memory use for downstream writes.
comment |
| 2022-10-01 | snowflake |
Restart of snowflake-server on the snowflake-01 bridge, with GOGC=200.
comment |
| 2022-09-30 to 2022-10-01 | snowflake |
Experiment with bypassing extor-static-cookie on the snowflake-01 bridge. Transport- and country-specific metrics were not collected on the bridge during this time.
issue |
| 2022-09-30 | snowflake |
Restart of snowflake-server on the snowflake-01 bridge with a mitigation for ephemeral port exhaustion.
comment |
| 2022-09-30 | snowflake |
Restart of snowflake-server on the snowflake-01 bridge to restore a dual-stack configuration.
comment |
| 2022-09-30 | snowflake |
Temporary outage of the snowflake-01 bridge caused by adjusting network interfaces.
comment |
| 2022-09-29 | snowflake |
Reboot of snowflake-01 bridge and restarts of the snowflake-server process for maintenance.
comment |
| 2022-09-29 to 2022-10-31 |
When Tor Metrics introduced a new method of counting clients (to work with multi-instance relays like the Snowflake bridge), it required reprocessing stats in the overlapping months.
issue |
|
| 2022-09-29 | snowflake |
Redeployed snowflake-server on the snowflake-01 bridge, in an attempt to reduce memory allocation.
comment commit |
| 2022-09-28 | snowflake |
Testing an alternative WebSocket package on the snowflake-01 bridge.
comment |
| 2022-09-27 |
Tor Metrics gains the ability to process descriptors from multi-instance relays (like the Snowflake bridge).
merge request issue |
|
| 2022-09-27 | snowflake |
Redeployed snowflake-server on the snowflake-01 bridge, reducing the per-client packet send queue size from 2048 to 512.
comment |
| 2022-09-26 | snowflake |
RAM upgrade on snowflake-01 bridge.
issue |
| 2022-09-26 | ir obfs4 snowflake |
Made Snowflake the preferred transport in Connection Assist for Iran (was obfs4).
merge request |
| 2022-09-24 | snowflake |
Increased the number of tor instances on the snowflake-01 bridge from 8 to 12.
comment mailing list post |
| 2022-09-24 | snowflake |
Redeployed snowflake-server on the snowflake-01 bridge, with further memory use optimizations.
comment |
| 2022-09-23 | snowflake |
Redeployed snowflake-server on the snowflake-01 bridge, reducing the keepalive timeout from 10 minutes to 4 minutes.
comment |
| 2022-09-23 | snowflake |
Redeployed snowflake-server on the snowflake-01 bridge, disabling profiling and raising the keepalive timeout from 2 minutes to 10 minutes.
comment |
| 2022-09-23 | snowflake |
Deployed memory use optimizations and enabled profiling on the snowflake-01 bridge. Reduced the keepalive timeout from 10 minutes to 2 minutes. Increased the size of the clientID-to-IP map from 10240 to 98304.
comment |
| 2022-09-22 | snowflake |
Increased the number of tor instances on the snowflake-01 bridge from 4 to 8.
mailing list post comment |
| 2022-09-21 to 2022-10-04 | Unknown Country |
Abnormal increase in estimated meek users, believed to be caused by an overloaded meek-azure bridge.
forum thread |
| 2022-09-21 to present | Iran |
Protests and daily Internet shutdowns in Iran.
OONI report BBS thread |
| 2022-08-25 | Turkmenistan snowflake |
Used an alternate STUN port number in Connection Assist for Snowflake in Turkmenistan, and represented STUN servers as IP addresses rather than hostnames.
merge request |
| 2022-08-12 |
Release of tor 0.4.5.14, 0.4.6.12 and 0.4.7.10, with a fix to the geoip database.
announcement |
|
| 2022-08-12 | ipv4 ipv6 |
geoip and geoip6 databases updated to "IPFire Project Tue, 09 Aug 2022 06:11:25 GMT" (geoip-db-digest 0AE7077313A53103C2B32100D74AAFC04216289D, geoip6-db-digest DCBF1789BF1EEB03276B830CB2AB92BCF779D97F).
commit |
| 2022-08-11 |
Release of tor 0.4.5.13, 0.4.6.11 and 0.4.7.9, with congestion control changes aimed at mitigating the DDoS attack that started 2022-06-06.
announcement |
|
| 2022-08-11 | ipv4 ipv6 |
geoip and geoip6 databases updated to "IPFire Project Thu, 11 Aug 2022 05:41:58 GMT" (geoip-db-digest A642DB3FC558C9C609159064A32CD4FBCA254CCA, geoip6-db-digest C8CB9E5727CCE1479D595EBFEF5D9AAC1C9B9E94).
commit |
| 2022-08-10 | ipv4 ipv6 |
geoip and geoip6 databases updated to "IPFire Project Fri, 17 Jun 2022 06:11:30 GMT" (geoip-db-digest C8CC32FB272CDC7D2C310839D3BE02C49053918D, geoip6-db-digest 0CC43D240A9A4B2B218A8A6DA20EA03EE0BB6912).
commit |
| 2022-08-05 | China obfs4 Unknown |
Sudden drop in access to bridges from the "https" pool from China.
comment bridge graph |
| 2022-07-30 | Indonesia |
Mass blocking of websites in Indonesia.
article |
| 2022-07-29 | Russia |
The domain www.torproject.org and its IP addresses are again blocked, after having been unblocked on 2022-07-14. Other subdomains of torproject.org remain unblocked.
record GitLab comment BBS comment zapret-info diff OONI measurements |
| 2022-07-14 | Bridges |
Release of Tor Browser 11.5, with a new Connection Assist feature for automatic censorship circumvention configuration.
blog post graph of effect on Snowflake initial country-specific settings initial default settings |
| 2022-07-14 | Russia |
The Tor Project web server block, which had begin on 2021-12-07, is lifted.
record GitLab comment BBS comment zapret-info diff OONI measurements |
| 2022-06-27 | snowflake |
Release of Snowflake WebExtension 0.6.0. The main feature added in this release was support for more than one bridge. It had a bug that caused it to stop reporting client IP addresses, which caused a fraction of Snowflake usage to be attributed to the unknown country ?? in metrics, rather than being properly geolocated.
archive merge request issue |
| 2022-06-17 |
Release of tor 0.4.7.8, fixing a DoS vulnerability relating to the new congestion control in 0.4.7.7 (TROVE-2022-001, CVE-2022-33903.
announcement issue |
|
| 2022-06-16 | snowflake |
Began periodic restarts of Snowflake's probetest NAT measurement service, which increased the success rate of proxies self-measuring their NAT type.
issue comment |
| 2022-06-06 to 2023-04-05 |
Network-wide DDoS attack.
status.torproject.org issue forum thread graph onion v3 traffic |
|
| 2022-05-23 |
Release of Tor Browser 11.0.13, the first stable release with congestion control.
blog post |
|
| 2022-05-12 | Uzbekistan meek Unknown |
meek users in Uzbekistan drop to zero.
issue bridge users graph |
| 2022-05-06 | snowflake |
Upgraded the network uplink of the Snowflake bridge from 1 Gbps to 10 Gbps.
issue |
| 2022-04-27 |
Release of tor 0.4.7.7, the first release with congestion control.
forum post blog post |
|
| 2022-04-12 | snowflake |
Stopped the tor instances flakey1–flakey8 on the interim Snowflake bridge, leaving only instances flakey1–flakey4 running on the new bridge.
comment |
| 2022-04-11 | snowflake |
Moved Snowflake traffic to a new bridge running instances flakey1–flakey4.
comment |
| 2022-04-11 to 2022-04-12 | Turkmenistan |
The intensity of Internet blocking in Turkmenistan increases. Some sources inside the country claim that "the Internet has been blocked almost completely".
NTC thread Access Now post Cloudflare Radar tweet |
| 2022-04-11 | snowflake |
Started a new Snowflake bridge running tor instances flakey1–flakey4, temporarily running in parallel with the interim bridge with its instances flakey1–flakey8.
comment |
| 2022-03-19 | snowflake |
Stopped the tor instances flakey1–flakey4 on the old Snowflake bridge, leaving only instances flakey1–flakey8 running on the interim bridge.
comment |
| 2022-03-18 | snowflake |
Restarted the interim Snowflake bridge to correct a problem with onion keys.
comment |
| 2022-03-16 | snowflake |
Moved Snowflake traffic to the interim bridge running instances flakey1–flakey8.
comment |
| 2022-03-15 | snowflake |
Started an interim Snowflake bridge running tor instances nicknamed flakey1–flakey8, temporarily running in parallel with the main bridge with its instances flakey1–flakey4.
comment |
| 2022-02-28 | Bridges |
BridgeDB moves to an rdsys backend.
announcement issue |
| 2022-02-24 to present | Russia Ukraine |
Russian invasion of Ukraine. In the following days, various social media are partially blocked in Russia. Bridge users increase in Russia; relay and bridge users increase in Ukraine.
Wikipedia Relay users in Russia Bridge users in Russia Relay users in Ukraine Bridge users in Ukraine OONI article |
| 2022-02-18 | snowflake |
Outage of the Snowflake bridge.
mailing list post alert failed alert succeeded |
| 2022-02-04 | ipv4 ipv6 |
geoip and geoip6 databases updated to "IPFire Project Fri, 04 Feb 2022 05:51:31 GMT" (geoip-db-digest C4F1B5ECF1B07BBECBE06B93926E4D1E62882782, geoip6-db-digest 0E43B5C62033BFE47F32742D8C9F5B5F83180AA4).
commit |
| 2022-02-01 |
Tor 0.3.5 reaches end of life.
mailing list post |
|
| 2022-01-31 | snowflake |
Switched the snowflake bridge from a load-balanced staging server back to the now load-balanced production server. Debugged connection problems until 2022-01-31 19:52:04.
issue comment comment |
| 2022-01-30 | snowflake |
Rebuilt the production bridge, which had run a single flakey instance, to run four instances flakey1–flakey4.
comment |
| 2022-01-28 | snowflake |
Switched the snowflake-server (at the time running on a load-balanced staging server) for a version with CPU profiling.
comment |
| 2022-01-25 | snowflake |
Switched the snowflake bridge to the temporary load-balanced staging server. Debugged connection problems until 2022-01-25 18:47:00.
issue comment post comment |
| 2022-01-24 | snowflake |
Started a temporary load-balanced Snowflake staging server running four instances flakey1–flakey4. Ran in parallel with the existing production instances (single flakey until 2022-01-30 04:51:00, flakey1–flakey4 thereafter) and the flakey1–flakey4 instances of the practice staging bridge until 2022-02-03 05:39:24.
comment |
| 2022-01-24 to 2022-02-10 | Uzbekistan Relays Unknown |
Temporary decrease in relay users in Uzbekistan.
relay users graph |
| 2022-01-17 to 2022-02-03 | snowflake |
Ran a practice Snowflake staging bridge with four instances flakey1–flakey4, initially in parallel with the production bridge running a single flakey instance.
comment mailing list post |
| 2022-01-12 to 2022-08-08 | webstats Unknown |
Tor Browser update pings drop temporarily. A similar effect is present in other years.
graph issue issue |
| 2022-01-11 to 2022-02-01 | Burkina Faso obfs4 Unknown |
Temporary spike in obfs4 users from Burkina Faso.
bridge users graph |
| 2022-01-10 | Kazakhstan obfs4 |
The Tor Project begins to distribute obfs4 bridges that listen on ports that are reachable in Kazakhstan, despite the ongoing Internet shutdown.
forum post |
| 2022-01-07 | snowflake |
Increased capacity of the mapping to client IP addresses on the snowflake bridge.
issue deployment comment |
| 2022-01-05 to 2022-01-11 | Kazakhstan |
Country-wide Internet shutdown in Kazakhstan. Was preceded by a shutdown of most mobile networks starting 2022-01-04 14:30. Access was restored for a few hours each day.
Cloudflare blog post RIPE Labs blog post NTC thread BBS thread IODA |
| 2022-01-04 | Gambia |
Internet outage in Gambia.
blog post |
| 2021-12-29 | snowflake |
Outage of the snowflake bridge.
comment alert failed alert succeeded |
| 2021-12-24 | Russia obfs4 |
Another round of obfs4 enumeration and blocking occurs in Russia.
comment |
| 2021-12-22 to present | Finland Relays Unknown |
Increase of relay users in Finland.
tor-talk thread possible explanation graph |
| 2021-12-22 | snowflake |
Rebooted the Snowflake bridge to increase the number of CPUs from 4 to 8.
issue |
| 2021-12-20 | snowflake |
Release of Tor Browser 11.0.3, with an altered DTLS fingerprint in Snowflake to counteract blocking in Russia.
blog post issue NTC post |
| 2021-12-15 | ipv4 ipv6 |
geoip and geoip6 databases updated to "IPFire Project Wed, 15 Dec 2021 06:07:42 GMT" (geoip-db-digest BE1D08BC7B80B1D94CC1B67E5F59CECE9D282F99, geoip6-db-digest E7C6C7875CF972346E01F8E87E87E77D939437DB).
commit |
| 2021-12-14 | snowflake |
Release of Tor Browser 11.5a1, with an altered DTLS fingerprint in Snowflake to counteract blocking in Russia.
blog post issue NTC post |
| 2021-12-13 | Russia |
The fraction of networks in Russia blocking Tor, measured by OONI, increases from about 20% to about 50%.
relay graph |
| 2021-12-08 | obfs4 |
Release of Tor Browser 11.0.2, containing a new default obfs4 bridge "deusexmachina".
blog post issue |
| 2021-12-08 | Russia |
The Tor Project web server block is expanded from *.www.torproject.org to *.torproject.org.
record GitLab comment NTC comment zapret-info diff |
| 2021-12-07 | Russia |
The www.torproject.org web server is added to the registry of blocked domain names in Russia, by IP addresses and by hostname *.www.torproject.org.
record GitLab comment NTC comment zapret-info diff OONI report |
| 2021-12-01 to 2021-12-13 | Russia meek |
Blocking of the IP address of the meek-azure front domain in certain ISPs in Russia, part of a wider phenomenon of blocking Tor beginning 2021-12-01.
post about start (2021-12-03) post about end (2021-12-13) post about end (2021-12-15) post about end (2021-12-26) |
| 2021-12-01 to present | Russia |
Blocking of Tor directory authorities, relays, default obfs4 bridges, meek-azure, and Snowflake in some ISPs in Russia. There was a temporary cease of blocking for less than a day starting on 2021-12-08.
NTC thread BBS thread issue blog post OONI report |
| 2021-11-22 to 2022-11-28 | Burkina Faso |
Shutdown of mobile Internet in Burkina Faso.
article relay users graph tweet |
| 2021-11-17 to 2022-02-02 | obfs4 |
Run a Tor Bridge campaign, offers rewards for running obfs4 bridges.
blog post about start blog post about end |
| 2021-10-03 to present | Egypt Relays Unknown |
Increase of relay users in Egypt.
Twitter thread relay graph |
| 2021-06-10 to present |
Experiment to test latencies between relays.
status.torproject.org post announcing start |
|
| 2021-06-04 to present | Nigeria |
Block of Twitter in Nigeria. Increase in the number of bridge users.
article relay graph bridge graph |
| 2021-04-01 to present | Myanmar |
Shutdowns of wireless broadband in Myanmar.
Access Now post |
| 2021-01-01 to present | China snowflake Unknown |
Increased failure to bootstrap using Snowflake from China.
comment |
| 2020-10-27 to present | Tanzania, United Republic of OR obfs4 |
Blocking of Tor and default obfs4 bridges during elections in Tanzania.
OONI report |
| 2019-06-21 to present | Myanmar |
Internet shutdown in parts of Myanmar.
report 2020 report |
| 2019-04-27 to present | Russia Relays Unknown |
Relay users increase by about 100K, in an apparent weekly cycle. Bridge users are not similarly affected.
relay graph bridge graph tor-talk thread Reddit thread |
| 2019-02-16 to present | Belarus Relays Unknown |
Increase of relay users in Belarus.
graph mailing list post |
| 2018-12-20 to present | Sudan |
Protests and social media blocks in Sudan.
relay graph Access Now post Psiphon users |
| 2018-09-26 to present | fte |
Outage of default FTE bridge 128.105.214.162:8080.
comment |
| 2018-09-26 to present | fte |
Outage of default FTE bridge 128.105.214.163:8080.
comment |
| 2018-07-28 to present | Turkey Relays Unknown |
Another jump of relay users in Turkey, from 5k to about 30k.
relay graph bridge graph |
| 2018-07-01 to present | Uganda |
A social media tax takes effect in Uganda. The government pressures ISPs to block VPNs.
relay graph bridge graph BBC article AllAfrica article OONI report |
| 2018-06-20 to present | Venezuela |
Venezuela's largest ISP, CANTV, blocks direct access to Tor and the IP addresses of default bridges. meek and non-default bridges are reported to work.
ticket mailing list post Access Now report |
| 2018-04-30 to present | Iran |
Iranian ISPs block Telegram.
ticket article relay graph bridge graph Psiphon users |
| 2018-01-05 to present |
Outage of the op-hk OnionPerf instance.
op-hk graph |
|
| 2017-12-04 to present |
DDoS attack creates load on the network.
tor-relays thread relay graph summary post ticket |
|
| 2017-08-07 to present | Congo, The Democratic Republic of the |
The Democratic Republic of the Congo orders a block of social media services.
article relay graph bridge graph |
| 2017-02-10 to present | OR exit |
Measurement error from bandwidth authority causes decrease in measured bandwidth in Europe.
mailing list post |
| 2016-12-15 to present | Congo, The Democratic Republic of the |
The Democratic Republic of the Congo orders a block of social media services.
article relay graph bridge graph |
| 2016-11-03 to present | Turkey |
Turkey blocks Facebook, Twitter, YouTube, WhatsApp.
article |
| 2016-10-25 to present | Egypt OR Relays |
Egypt blocks Tor directory authorities and public relays by TCP RST. Bridges work.
OONI report |