To Know: Re-Do problems (if desired) are on canvas for Module 1 and 2. Due Monday.

To Do: In the EC Digital Signature algorithm we studied, I mentioned that if k is re-used, there’s an attack. Suppose you see Alice sign two messages: (m1,R,s1) and (m2,R,s2). Because R is the same, you know she used the same k. Explain how to obtain k. Then explain how to use that to obtain her secret key. (Note: if it helps, you can assume the order of P is prime, at first.) Hand in on canvas.