Using p=3, q=13, d=7 and e=3 in the RSA algorithm, what is the value of…
2015
Using p=3, q=13, d=7 and e=3 in the RSA algorithm, what is the value of ciphertext for a plain text 5?
- A.
8
- B.
21
- C.
26
- D.
33
Attempted by 89 students.
Show answer & explanation
Correct answer: A
Solution:
Compute n = p × q = 3 × 13 = 39.
Encryption uses cipher text c = m^e mod n with m = 5 and e = 3.
Calculate 5^3 = 125.
Reduce modulo 39: 125 mod 39 = 125 − 39 × 3 = 125 − 117 = 8.
Therefore the cipher text is 8.
Loading lesson…