Question

In electronic code book mode:

A) Blocks are encrypted independently.
B) An attacker can potentially reorder the ciphertext blocks without detection.
C) It is a deterministic encryption scheme.
D) All of the above

Answer 1

In electronic code book mode, each block of plaintext is encrypted independently and it is a deterministic encryption scheme.

Step-by-step explanation:

In electronic code book mode, each block of plaintext is encrypted independently to produce a corresponding block of ciphertext. This means that each block is encrypted using the same key and the same encryption algorithm. So, option A: Blocks are encrypted independently, is correct.

Now, let's consider option B: An attacker can potentially reorder the ciphertext blocks without detection. This statement is not true for electronic code book mode. Since each block is encrypted independently, reordering the ciphertext blocks won't affect the decrypted message. Therefore, option B is not correct.

Finally, option C: It is a deterministic encryption scheme. This statement is true for electronic code book mode. Deterministic encryption means that the same plaintext block will always encrypt to the same ciphertext block, given the same key and encryption algorithm. So, option C is correct.

In conclusion, the correct answer is option A and option C: Blocks are encrypted independently and it is a deterministic encryption scheme.