Protocol Game

In case you've missed them, check first the introduction.

Interactive game

Let us consider now the following protocol:

Knowledge: A:[s, KAS, A, B], B:[KBS, A, B], S:[A, B, E, KAS, KBS, KES] E:[A, B, KES, fake]
Steps:

  1. A -> S: A, B
  2. S -> A: {KBS}KAS
  3. A -> B: {#s}KBS

Can you figure out a way for E to know the session secret? Can you figure out a way for B to know "fake"?

Network stack

Commands


The next exercise considers a more complex server key protocol.