I hope someone can help me with the sequence of games security proof for protocols. Here are my questions:
What is the aim of each individual game? i.e. why can't we do this in one indistinguishable game ?
How can we link each game with the previous one? i.e. I am not understanding the difference lemma which states:
Lemma 1 (Difference Lemma). Let A, B, F be events defined in some probability distribution, and suppose that A ∧ ¬F ⇐⇒ B ∧ ¬F. Then |Pr[A] − Pr[B]| ≤ Pr[F].