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Roger Dingledine - How Russia is trying to block Tor
Presentation Title: How Russia is trying to block Tor
Roger Dingledine, The Tor Project
he/him
Length of presentation: 45 minutes.
Tool Release
In December 2021, some ISPs in Russia started blocking Tor's website,
along with protocol-level (DPI) and network-level (IP address) blocking to
try to make it harder for people in Russia to reach the Tor network. Some
months later, we're now at a steady-state where they are trying to find
new IP addresses to block and we're rotating IP addresses to keep up.
In this talk I'll walk through what steps the Russian censors have taken,
and how we reverse engineered their attempts and changed our strategies
and our software. Then we'll discuss where the arms race goes from here,
what new techniques the anti-censorship world needs if we're going to
stay ahead of future attacks, and what it means for the world that more
and more countries are turning to network-level blocking as the solution
to their political problems.
Speaker Bio(s):
Roger Dingledine is president and co-founder of the Tor Project, a
nonprofit that develops free and open source software to protect people
from tracking, censorship, and surveillance online.
Wearing one hat, Roger works with journalists and activists on many
continents to help them understand and defend against the threats they
face. Wearing another, he is a lead researcher in the online anonymity
field, coordinating and mentoring academic researchers working on
Tor-related topics. Since 2002 he has helped organize the yearly
international Privacy Enhancing Technologies Symposium (PETS).
Among his achievements, Roger was chosen by the MIT Technology Review
as one of its top 35 innovators under 35, he co-authored the Tor design
paper that won the Usenix Security "Test of Time" award, and he has
been recognized by Foreign Policy magazine as one of its top 100 global
thinkers.
Twitter: @RogerDingledine is me, @TorProject is Tor
REFERENCES:
The original "blocking resistance" Tor design paper with our original goals:
https://www.freehaven.net/anonbib/#tor-blocking
Tor Pluggable Transport Specification:
https://spec.torproject.org/pt-spec
The obfs4 protocol specification:
https://gitweb.torproject.org/plugga...obfs4-spec.txt
Three blog posts that build on each other, describing building blocks
we need for smarter bridge distribution:
https://blog.torproject.org/strategi...idge-addresses
https://blog.torproject.org/research...er-tor-bridges
https://blog.torproject.org/research...e-reachability
A research paper outlining a neat way to automatically steer bridge
resources toward distribution channels that are succeeding:
https://www.freehaven.net/anonbib/#proximax11
Three research papers describing trust-based bridge distribution approaches:
https://www.freehaven.net/anonbib/#salmon-pets2016
https://www.freehaven.net/anonbib/#ndss13-rbridge
https://patternsinthevoid.net/hyphae/hyphae.pdf
David Fifield's PETS 2013 paper, on various tricks that can be used for
signaling -- like domain fronting but more varied than domain fronting:
https://www.freehaven.net/anonbib/#pets13-oss
David Fifield's thesis explaining meek and other things:
https://www.bamsoftware.com/papers/thesis/
Open Observatory for Network Interference (OONI):
https://ooni.torproject.org/
Snowflake website and documentation:
https://snowflake.torproject.org/
The Conjure paper, which describes (aside from the refraction networking
part) the idea of having a "middle service" that pretends to be many
different end-point services, as a way to scale to running obfs4 bridges
or Snowflakes on many thousands of addresses at once:
https://ericw.us/trow/conjure-ccs19.pdf
[]
Presentation Title: How Russia is trying to block Tor
Roger Dingledine, The Tor Project
he/him
Length of presentation: 45 minutes.
Tool Release
In December 2021, some ISPs in Russia started blocking Tor's website,
along with protocol-level (DPI) and network-level (IP address) blocking to
try to make it harder for people in Russia to reach the Tor network. Some
months later, we're now at a steady-state where they are trying to find
new IP addresses to block and we're rotating IP addresses to keep up.
In this talk I'll walk through what steps the Russian censors have taken,
and how we reverse engineered their attempts and changed our strategies
and our software. Then we'll discuss where the arms race goes from here,
what new techniques the anti-censorship world needs if we're going to
stay ahead of future attacks, and what it means for the world that more
and more countries are turning to network-level blocking as the solution
to their political problems.
Speaker Bio(s):
Roger Dingledine is president and co-founder of the Tor Project, a
nonprofit that develops free and open source software to protect people
from tracking, censorship, and surveillance online.
Wearing one hat, Roger works with journalists and activists on many
continents to help them understand and defend against the threats they
face. Wearing another, he is a lead researcher in the online anonymity
field, coordinating and mentoring academic researchers working on
Tor-related topics. Since 2002 he has helped organize the yearly
international Privacy Enhancing Technologies Symposium (PETS).
Among his achievements, Roger was chosen by the MIT Technology Review
as one of its top 35 innovators under 35, he co-authored the Tor design
paper that won the Usenix Security "Test of Time" award, and he has
been recognized by Foreign Policy magazine as one of its top 100 global
thinkers.
Twitter: @RogerDingledine is me, @TorProject is Tor
REFERENCES:
The original "blocking resistance" Tor design paper with our original goals:
https://www.freehaven.net/anonbib/#tor-blocking
Tor Pluggable Transport Specification:
https://spec.torproject.org/pt-spec
The obfs4 protocol specification:
https://gitweb.torproject.org/plugga...obfs4-spec.txt
Three blog posts that build on each other, describing building blocks
we need for smarter bridge distribution:
https://blog.torproject.org/strategi...idge-addresses
https://blog.torproject.org/research...er-tor-bridges
https://blog.torproject.org/research...e-reachability
A research paper outlining a neat way to automatically steer bridge
resources toward distribution channels that are succeeding:
https://www.freehaven.net/anonbib/#proximax11
Three research papers describing trust-based bridge distribution approaches:
https://www.freehaven.net/anonbib/#salmon-pets2016
https://www.freehaven.net/anonbib/#ndss13-rbridge
https://patternsinthevoid.net/hyphae/hyphae.pdf
David Fifield's PETS 2013 paper, on various tricks that can be used for
signaling -- like domain fronting but more varied than domain fronting:
https://www.freehaven.net/anonbib/#pets13-oss
David Fifield's thesis explaining meek and other things:
https://www.bamsoftware.com/papers/thesis/
Open Observatory for Network Interference (OONI):
https://ooni.torproject.org/
Snowflake website and documentation:
https://snowflake.torproject.org/
The Conjure paper, which describes (aside from the refraction networking
part) the idea of having a "middle service" that pretends to be many
different end-point services, as a way to scale to running obfs4 bridges
or Snowflakes on many thousands of addresses at once:
https://ericw.us/trow/conjure-ccs19.pdf
[]