The ciphertext message produced by the knapsack cryptosystem employing the superincreasing sequence 1, 3, 5, 11, 35, modulus m = 73, and multiplier a = 5 is 55, 15, 124, 109, 25, 34. Obtain the plaintext message.
Step 11 of 2
A ciphertext message produced by the knapsack cryptosystem employing the super increasing sequence , modulus , and multiplier , is
The knapsack sequence was arrived at by multiplying with the original plaintext code. To reverse the process, we multiply with such that
Such an is given by . We multiply each number by modulo to get:
Now, express all these numbers by the superincreasing sequence above:
This gives the binary sequence:
Converting this to letters we arrive at the plaintext message