Tor Browser's default bridges

Tor Browser ships with a number of default bridges. These bridges are hard-coded in the file ​bridge_prefs.js. The following table is meant to be an authoritative list of our default bridges plus the people who operate these bridges. Whenever we add, remove, or change any of our default bridges, make sure to commit this change to the following repositories:

• ​tor-browser-build
• ​tor-android-service
• ​onionbrowser
• ​Orbot (​Orbot fa)
• ​OONI

Also, use the tbb-bridges trac keyword for new tickets related to default bridges.

Type	IP:port	Fingerprint	Parameters	Contact	URL	Status
obfs4	38.229.1.78:80	C8CBDB2464FC9804A69531437BCF2BE31FDD2EE4	cert=Hmyfd2ev46gGY7NoVxA9ngrPF2zCZtzskRTzoWXbxNkzeVnGFPWmrTtILRyqCTjHR+s9dg iat-mode=1	Sina Rabbani <srabbani@…>	​Mailing list
obfs4	38.229.33.83:80	0BAC39417268B96B9F514E7F63FA6FBA1A788955	cert=VwEFpk9F/UN9JED7XpG1XOjm/O8ZCXK80oPecgWnNDZDv5pdkhq1OpbAH0wNqOT6H6BmRQ iat-mode=1	Sina Rabbani <srabbani@…>	​Mailing list
obfs4	[2001:470:b381:bfff:216:3eff:fe23:d6c3]:443	CDF2E852BF539B82BD10E27E9115A31734E378C2	cert=qUVQ0srL1JI/vO6V6m/24anYXiJD3QP2HgzUKQtQ7GRqqUvs7P+tG43RtAqdhLOALP7DJQ iat-mode=1	David Goulet <dgoulet@…>	#22429	​Metrics
obfs4	192.95.36.142:443	CDF2E852BF539B82BD10E27E9115A31734E378C2	cert=qUVQ0srL1JI/vO6V6m/24anYXiJD3QP2HgzUKQtQ7GRqqUvs7P+tG43RtAqdhLOALP7DJQ iat-mode=1	David Goulet <dgoulet@…>	#22429	​Metrics
obfs4	37.218.240.34:40035	88CD36D45A35271963EF82E511C8827A24730913	cert=eGXYfWODcgqIdPJ+rRupg4GGvVGfh25FWaIXZkit206OSngsp7GAIiGIXOJJROMxEqFKJg iat-mode=1	Mart van Santen <mart@…>	#22468	​Metrics
obfs4	37.218.245.14:38224	D9A82D2F9C2F65A18407B1D2B764F130847F8B5D	cert=bjRaMrr1BRiAW8IE9U5z27fQaYgOhX1UCmOpg2pFpoMvo6ZgQMzLsaTzzQNTlm7hNcb+Sg iat-mode=0	Mart van Santen <mart@…>	#22468	​Metrics
obfs4	85.31.186.98:443	011F2599C0E9B27EE74B353155E244813763C3E5	cert=ayq0XzCwhpdysn5o0EyDUbmSOx3X/oTEbzDMvczHOdBJKlvIdHHLJGkZARtT4dcBFArPPg iat-mode=0	Felix <zwiebel@…>	#23166	​Metrics
obfs4	85.31.186.26:443	91A6354697E6B02A386312F68D82CF86824D3606	cert=PBwr+S8JTVZo6MPdHnkTwXJPILWADLqfMGoVvhZClMq/Urndyd42BwX9YFJHZnBB3H0XCw iat-mode=0	Felix <zwiebel@…>	#23166	​Metrics
obfs4	216.252.162.21:46089	0DB8799466902192B6C7576D58D4F7F714EC87C1	cert=XPUwcQPxEXExHfJYX58gZXN7mYpos7VNAHbkgERNFg+FCVNzuYo1Wp+uMscl3aR9hO2DRQ iat-mode=0	Noisebridge	#24756	​Metrics
obfs4	144.217.20.138:80	FB70B257C162BF1038CA669D568D76F5B7F0BABB	cert=vYIV5MgrghGQvZPIi1tJwnzorMgqgmlKaB77Y3Z9Q/v94wZBOAXkW+fdx4aSxLVnKO+xNw iat-mode=0	Louis-Philippe Véronneau <pollo@…>	#28185	​Metrics
meek	0.0.2.0:2	97700DFE9F483596DDA6264C4D7DF7641E1E39CE	url=https://meek.azureedge.net/ front=ajax.aspnetcdn.com	Sina Rabbani <srabbani@…>	#21342	​Metrics
snowflake	0.0.3.0:1	2B280B23E1107BB62ABFC40DDCC8824814F80A72	N/A	David Fifield <david@…>	N/A	​Metrics

Adding new default bridges

The following is an informal list of requirements that we have for default bridges:

• A reliable network link that can handle at least a sustained 100 Mbit/s of traffic.
  • Any modern CPU can sustain at least 100 MBit/s. A CPU with the AES-NI extension is particularly helpful because it allows Tor to offload its AES operations to the CPU.
  • We recommend 4 GB of RAM for 100 MBit/s.
  • For more than 100 MBit/s, a second core may be necessary and more than 4 GB of RAM.
• We would like to personally know you (or somebody who is involved in the bridge's operation).
  • You should also have a sustainable plan for running the bridge, so it doesn't get abandoned.
• It's useful (but not necessary) for the bridge to have a dedicated IP address because this IP address will get blocked by China and other places.
  • If you don't have a dedicated IP address, don't host any services on the bridge that you don't want to see blocked in some countries or networks.
• You shouldn't also be running an exit relay.
• You should give us at least a one month notice before they shut down their bridge.

Tickets related to default bridges

Ticket	Summary	Status	Owner	Keywords	Priority
#13727	BridgeDB should not distribute Tor Browser's default bridges	assigned		bridgedb-dist, tbb-bridges, anti-censorship-roadmap-september	Medium
#17449	Test bridges we ship in Tor Browser regularly	new	boklm	tbb-usability, tbb-bridges	Medium
#18113	Dynamically allocate clients to default Tor Browser bridges of a certain type	needs_information	brade	tbb-bridges	Medium
#29275	Get default bridges checked for reachability by OONI	new		tbb-bridges, ex-sponsor-19	Medium
#30121	Create authoritative, parseable list of Tor Browser's default bridges	assigned	phw	tbb-bridges	Medium
#30264	Revise list of default Tor Browser bridges	assigned	phw	tbb-bridges	Medium
#30794	Create lightweight censorship analyser for users	assigned	phw	tbb-bridges	Medium
#30870	Default obfs4 bridges are all offline	needs_information	n8fr8	tbb-bridges	Medium
#31164	Set up default bridge at Karlstad University	assigned	phw	tbb-bridges	Medium
#31523	Recruit potential default bridges from set of long-running bridges	new		tbb-bridges	Medium