Introduction to Tor

and

The Tor Software Ecosystem

Sukhbir Singhsukhbir@torproject.org

August 9, 2017

Anonymity on the Internet

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Anonymity on the Internet

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Anonymity on the Internet

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Anonymity on the Internet

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Anonymity on the Internet

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Anonymity on the Internet

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Anonymity on the Internet

Anonymity

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Anonymity on the Internet

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“On the Internet, Nobody Knows...”

†

†Image from The New Yorker cartoon by Peter Steiner, 1993

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On the Internet, They Know...

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Tor: The Onion Router

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Tor: The Onion Router

Client

Destination

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Tor: The Onion Router

Client

Destination

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Tor: The Onion Router

Client

Destination

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Tor: The Onion Router

Client

Destination

Entry Guard (I)

Middle Relay (II) Exit Relay (III)

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Tor: The Onion Router

Client

Destination

Entry Guard (I)

Middle Relay (II) Exit Relay (III)

EntryMiddleExit

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Tor: The Onion Router

Client

Destination

Entry Guard (I)

Middle Relay (II) Exit Relay (III)

✓Source [IP]

× Destination [Resource]

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Tor: The Onion Router

Client

Destination

Entry Guard (I)

Middle Relay (II) Exit Relay (III)

× Source [IP]

✓Destination [Resource]

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Tor: The Onion Router

I Low-latency anonymity

I Distributed design

I 2,000,000 users and 6000 relaysI 100 Gbit/sec available bandwidth

∗https://metrics.torproject.org6 / 29

Tor: The Onion Router

I Low-latency anonymity

I Distributed design

I 2,000,000 users and 6000 relaysI 100 Gbit/sec available bandwidth

∗https://metrics.torproject.org6 / 29

Tor: The Onion Router

I Low-latency anonymity

I Distributed design

I 2,000,000 users and 6000 relaysI 100 Gbit/sec available bandwidth

∗https://metrics.torproject.org6 / 29

Who Uses Tor?

I Journalists

I Activists

I You...

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Who Uses Tor?

I Journalists

I Activists

I You...

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Who Uses Tor?

I Journalists

I Activists

I You...

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Who Uses Tor?

I Journalists

I Activists

I You...

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Tor vs. VPN

† VPN Tor Tor Browser

Censorship Evasion ++ +++ +++Appear Elsewhere ++ + +Anonymity + ++ +++Privacy − + +++Speed ++ −− −−Cost −− +++ +++

†Modified under CC BY-SA 4.0. Original work by Tim Sammut from

https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html

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Tor vs. VPN

† VPN Tor Tor BrowserCensorship Evasion ++ +++ +++

Appear Elsewhere ++ + +Anonymity + ++ +++Privacy − + +++Speed ++ −− −−Cost −− +++ +++

†Modified under CC BY-SA 4.0. Original work by Tim Sammut from

https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html

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Tor vs. VPN

† VPN Tor Tor BrowserCensorship Evasion ++ +++ +++Appear Elsewhere ++ + +

Anonymity + ++ +++Privacy − + +++Speed ++ −− −−Cost −− +++ +++

†Modified under CC BY-SA 4.0. Original work by Tim Sammut from

https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html

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Tor vs. VPN

† VPN Tor Tor BrowserCensorship Evasion ++ +++ +++Appear Elsewhere ++ + +Anonymity + ++ +++

Privacy − + +++Speed ++ −− −−Cost −− +++ +++

†Modified under CC BY-SA 4.0. Original work by Tim Sammut from

https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html

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Tor vs. VPN

† VPN Tor Tor BrowserCensorship Evasion ++ +++ +++Appear Elsewhere ++ + +Anonymity + ++ +++Privacy − + +++

Speed ++ −− −−Cost −− +++ +++

†Modified under CC BY-SA 4.0. Original work by Tim Sammut from

https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html

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Tor vs. VPN

† VPN Tor Tor BrowserCensorship Evasion ++ +++ +++Appear Elsewhere ++ + +Anonymity + ++ +++Privacy − + +++Speed ++ −− −−

Cost −− +++ +++

†Modified under CC BY-SA 4.0. Original work by Tim Sammut from

https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html

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Tor vs. VPN

† VPN Tor Tor BrowserCensorship Evasion ++ +++ +++Appear Elsewhere ++ + +Anonymity + ++ +++Privacy − + +++Speed ++ −− −−Cost −− +++ +++

†Modified under CC BY-SA 4.0. Original work by Tim Sammut from

https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html

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little-t-tor

I Core of the Tor software ecosystem

I Runs as a daemon and sets up a local SOCKS5 proxy†

I Platform support: Linux, macOS, Windows, BSD variants

†localhost:90509 / 29

little-t-tor

I Core of the Tor software ecosystem

I Runs as a daemon and sets up a local SOCKS5 proxy†

I Platform support: Linux, macOS, Windows, BSD variants

†localhost:90509 / 29

little-t-tor

I Core of the Tor software ecosystem

I Runs as a daemon and sets up a local SOCKS5 proxy†

I Platform support: Linux, macOS, Windows, BSD variants

†localhost:90509 / 29

Tor Browser

Tor Browser (Bundle)https://www.torproject.org/torbrowser

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Onion Services

Onion Service

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Onion Services

Onion Service

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Onion Services

Onion Service

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Onion Services

Onion Service

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Tor Software Ecosystem

Tor is not just Tor Browser!

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HTTPS Everywhere

Browser Extension for Enabling HTTPShttps://www.eff.org/https-everywhere

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Orbot and Orfox

Tor and Tor Browser on Androidhttps://guardianproject.info/

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Tails

Secure Operating Systemhttps://tails.boum.org/

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torsocks

$ . torsocks on

Wrapper to Torify Applicationshttps://gitweb.torproject.org/torsocks.git

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Ricochet

Anonymous P2P Instant Messaging Clienthttps://ricochet.im/

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Tor Messenger

Chat Client with native Tor and OTR Supporthttps://trac.torproject.org/projects/tor/wiki/doc/TorMessenger

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TorBirdy

Thunderbird Extension for Secure Email Communicationhttps://trac.torproject.org/projects/tor/wiki/torbirdy

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Pluggable Transports

Obfuscate Tor Traffichttps://www.torproject.org/docs/pluggable-transports.html.en

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Metrics

0

500 000

1 000 000

1 500 000

2 000 000

2 500 000

Jun−2017 Jul−2017 Aug−2017

The Tor Project − https://metrics.torproject.org/

Directly connecting users

Tor Network Metricshttps://metrics.torproject.org/

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Stem

Python Controllerhttps://stem.torproject.org/

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Nyx

Tor CLI Monitorhttps://nyx.torproject.org/

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txtorcon

Twisted-based Python Asynchronous Controllerhttps://github.com/meejah/txtorcon

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OONI

Open Observatory of Network Interferencehttps://ooni.torproject.org/

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Check

Test Your Network Settingshttps://check.torproject.org/

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SecureDrop

Open-source Whistleblower Submission Systemhttps://securedrop.org/

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GetTor

torproject.org blocked?

gettor@torproject.org

Provides Alternative Access to Tor Project Softwarehttps://gettor.torproject.org/

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Thank You

Come hack with us!https://www.torproject.org/getinvolved/

sukhbir@torproject.org

E4AC D397 5427 A5BA 8450 A1BE B01C 8B00 6DA7 7FAA

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