Question

Using playfair cipher, encrypt the plaintext “SUCCESS” using the keyword “MIDTERMEXAM”

Answer 1

Rules :

==> First, a plaintext message is split into pairs of two letters (digraphs). If there is an odd number of letters, a Z is added to the last letter.

==> The rules of encryption are −

• If both the letters are in the same column, take the letter below each one .
• If both letters are in the same row, take the letter to the right of each one .

==> If neither of the preceding two rules are true, form a rectangle with the two letters and take the letters on the horizontal opposite corner of the rectangle

encrypt the plaintext “SUCCESS”

using the keyword “MIDTERMEXAM”

M   I   D   T E R   X   A   B C F   G   H   K L N   O   P   Q   S U   V   W   Y   Z

==> NZRALCOCOC