Secrets

• T can prepare data for which he knows an itinerary

• Or he can prepare a legitimate encryption of the real map

• But he can't do both at once

  • Because he doesn't know an itinerary for the real map

• But he doesn't know ahead of time what V will ask for

• No matter what T does, V will catch him 50% of the time

• If they play two rounds of this game, V will catch T 75% of the time