Simulation: Mixnets

I'll be more enthusiastic about encouraging thinking outside the box when there's evidence of any thinking going on inside it. ~ Terry Pratchett ^[1]

http://mercutio531.deviantart.com/art/TARDIS-204908544

Three different sizes of envelopes (such that the smallest fits the medium-size and medium-size fits the largest envelope). The envelopes need either be of different colour or feature coloured dots for easy observation. Add a message to a small envelope, the small envelope is placed in a medium size envelope, and that one in a large size envelope.
Opaque containers (bags or cardboard boxes).
Colored ropes.

Roles

Enough people willing to play the parts

a network of at least 12 people holding boxes as mixnodes. People can be source and destination.
3 extra destinations (services on servers).
Depending on what situation you are translating, a few people are playing ISP observers (those infamous black boxes placed at ISP's). For example, for creating a situation like in Egypt, have one ISP (that is directly talking to government).
Some people playing governments
Everybody not in one of the above roles can be observers, of which some report to governments.

	
      _____________              +---------+   _____________                       _____________                  _____________                _____________            
      |           |        +----------+   /|   |           |        +----------+   |           |                  |           |                |           |
      |           |   +----------+   /|__/ |   |           |   +----------+   /|   |           |   +----------+   |           |                |           |
      |           |   |\        /|__/ |_\__|   |           |   |\        /|__/ |   |           |   |\        /|   |           |                |           |
      |___________|   | \______/ |_\__|        |___________|   | \______/ |_\__|   |___________|   | \______/ |   |___________|                |___________|
        _|_____|_     |__/____\__|               _|_____|_     |__/____\__|          _|_____|_     |__/____\__|     _|_____|_                    _|_____|_
       / ******* \ ............................ / ******* \ ....................... / ******* \ .................. / ******* \ ................ / ******* \
      / ********* \                            / ********* \                       / ********* \                  / ********* \                / ********* \
     ---------------                          ---------------                     ---------------                ---------------              ---------------

Scenarios

Mixnets

See concepts of mix networks: As a getting started mixnet scenario you can use:

A few people make messages (message in smallest envelope, smallest envelope in medium sized envelope, and that one in the largest envelope) and place them in mixnodes (at random).
When having three messages in their box mix nodes remove one envelope for each message and distributed each message to a new mix node. If a mix node sees the final recipient of a message that message is forwarded to its destination.

Just have people send messages back and forth at different times to get the network in a "running state" with a clear "baseline" of observations.

Now ask the observers to focus on three senders to determine who gets whose message. And what else seems noteworthy. Play with mixnet parameters and scenarios.

Onion routing

Set up a simulated Tor network. Use colored ropes to represent circuits.
Change routes (for the sake of the simulation every 3 minutes)
Have Cathy send Heathcliff a message. Can people in the room see that it was Cathy who passed a message to Heathcliff?
What if there are multiple messages being passed, can we still see?
What if a country creates their own national internet and we set up Tor in this country? What if (policing or intelligence agencies) of countries share what they see?

Garlic routing

The challenge: build a simulation for I2P.

Resources

References

↑ Terry Pratchett https://www.goodreads.com/author/show/1654.Terry_Pratchett