Editing Zero-knowledge proof (section)

==== Soundness ====
If Peggy does not know the information, then she can guess which question Victor will ask and generate either a graph isomorphic to {{mvar|G}} or a Hamiltonian cycle for an unrelated graph, but since she does not know a Hamiltonian cycle for {{mvar|G}}, she cannot do both. With this guesswork, her chance of fooling Victor is {{math|2<sup>−{{var|n}}</sup>}}, where {{mvar|n}} is the number of rounds. For all realistic purposes, it is infeasibly difficult to defeat a zero-knowledge proof with a reasonable number of rounds in this way.