Privacy Protection of IoT Based on Fully Homomorphic Encryption

Algorithm 2

Bit-extraction .

Input: Modulus , and a ciphertext c encrypting a constant relative to secret key s and modulus

Output: A ciphertext encrypting the bit operation relative to secret key s and modulus

1. Set // encrypt w.r.t. s

2. For to

3.Set // is an accumulator

4.For to //Compute

5.Set //Homomorphic exponentiation to the power

6.Set

7. Set // encrypts

8. Output