Question

(8) Suppose that Samantha is using the Elgamal signature scheme and that she is careless and uses the same random element k to sign two documents D and D (6) Explain how Evan can tell at a glance whether Samantha has made this mistake (ii) If the signature on D is (S1, S2) and the signature on D' is (St, S2), explain how Evan can recover a, Samanthas private signing key. (ii) Apply your method fr) to the following example and recover Samanthas signing key a, where Samantha is using the prime p 348149, base 113459, and verification key A 185149. D 153405, Si-208913, S2 209176 D'- 127561, S-208913, S2- 217800

Answer 1

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Solulidns by chackina which one eids