Question

(5) More Elgamal digital signatures. (2 pts for each correct answer) Samant ha uses the Elgamal signature scheme with prime p-6961 and primitive root g 437. Her public verification key is A 4250. Adam claims that Samantha has signed each of the documents D- 152, D' 1837, D 1614 and that the associated signatures are (s, sa) = (4129,5575), (Si,Sa) = (3145, 1871), (Si,S2)- (2709,2994). Which of these are valid signatures?

Answer 1

CYCLES Comp ufe ว้เ sa l C vate Key 2 2X a u e ap e

p6961 6961, 93 so) K is mod (6961) 23 SS7S 4129 1423 3998 23 | 1837208 3115 1871

2So tu0 (S,,S)= (0709/ 299 y) H (m) 1b1 1blY 29 9 y M So)2709 (3782) X. SSoy not verified )8귀