How to Tor

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Why are people interested in Tor?

  • Foreign and feeling very surveilled
  • Want to keep public internet presence separate from private
  • Just interested
  • Sensitive advocacy
  • Learn more about possible practical use cases

Why should we care about privacy?

  • What do we mean by our “fingerprint”? Why should we care?
  • I just get paranoid; want to be able to keep some data private
  • Your behavior can be analyzed
  • You can be profiled and lumped into groups


  • The basic digital identifier we’re concerned about today is your IP address
  • Internet runs on a request/response cycle
  • Assume all the space between our computer and our target server is hostile
  • E.g. infrastructure could be run by AT&T (spied on by the NSA)
  • Need to assume both the 1) address and 2) the content of the message are sensitive and need to be protected
  • Tor: The Onion Router
    • Metaphor of the layered onion to describe layers of encryption
    • Alice wants to send a message to Bob
      • Alice sends a request to the Tor directory (also the weak link)
      • Tor directory returns a list of “relay node” servers capable of relaying encrypted messages to other relay nodes in the Tor network
      • Given the addresses returned from the Tor directory, Alice’s computer chooses a random path through N relay nodes, to an “exit node” then finally out of the Tor network to Bob
      • Alice encrypts the information n times (n = number of nodes)
      • Each node knows
      • Where the packet came from
      • Where the packet is going
      • How to decrypt its one layer
      • The last node (exit node) knows the IP address of the target end point
  • Any UNIX-like system: `torify ssh [i.p.]` will torify your connection and show you connecting from a random IP address

Installating the Tor Browser

  • Open your favorite browser
  • Search for Tor (duckduckgo!)
  • Downloading Tor will sometimes give you a pgp key to verify the authenticity of the download
  • “GPG tools” is a thin wrapper for pgp tools:
  • Drag Tor into your apps folder
  • Choose whether you need to configure a Tor bridge node or not
  • “Which of the following best describes your situation?”
  • I would like to make a direct connection to the Tor network
  • My connection is censored or proxied. I need to configure bridge or local proxy settings before
  • Option 1 works for mostly free internet; option 2 is for more highly censored connections
  • We pick the first option because we have pretty good, clean internet

Now let’s use it!


  • Examples of VPNs
  • Note: VPN vs. proxy: proxy has 2 meanings
  • When we talked about VPNs, we really meant proxies
  • 2ndary (older-school original) meaning is the way to remotely connect to intranets