[Question][Hw2]

[anisrashidov]

Name: Anis Rashidov.

Just to confirm that I understood the material. My question is that snippet#1 below is AES for only one block encryption, while snippet#2 is AES for the whole message, right? Also, should we consider space (' ') as a character and encrypt it as well, or should we simply skip it?
Thanks in advance.

[KAIST-JongchanPark]

1. Yes
2. You should encrypt any character.(i.e. includes space, newline, ...)

[bongjunj]

1. AES module enc/decrypts a block. ECB, CBC, and CTR defines how to enc/decrypt a list of block using AES.
2. Every character is encoded into a byte (or bytes). And there are many ways to encode a character. The popular one is ASCII and UTF-8. Note that an encryption scheme is character-encoding agnostic.

[anisrashidov]

1. AES module enc/decrypts a block. ECB, CBC, and CTR defines how to enc/decrypt a list of block using AES.
2. Every character is encoded into a byte (or bytes). And there are many ways to encode a character. The popular one is ASCII and UTF-8. Note that an encryption scheme is character-encoding agnostic.

Don't we use ASCII in this assignment?

[tanapthetimid]

It doesn't matter what encoding we use here because we are encrypting the raw byte data.

[anisrashidov]

It doesn't matter what encoding we use here because we are encrypting the raw byte data.

Yeah, but what about converting human-readable text to binary string?

[KAIST-JongchanPark]

We usually encrypt a plaintext with human-readable characters.

However, in general, enc/dec mechanism doesn't care about whether input plaintext is human-readable or not.