Basics

Using AES, we can handle only 128 bit of pain text.

notation

Pain Text -> PT

Cypher Text -> CT

Cypher Key -> CK

ECB(Electronic Code Block)

PT1 PT2 … PTn with same CK

CBC(Cipher Block Chaining)

add IV(Initialization Vector) and loop

1. [PT1] XOR IV
2. (1) encrypt with CK
3. [PT2] XOR (2)
4. (3) encrypt with CK

Do it until PTn

CFB(Cipher FeedBack)

OFB(Output FeedBack)

CTR(CounTeR)

Galois Counter Mode

produce Tag(MAC) and CT

with AEAD(Authentication Encryption with Associated Data)

GCM plus steps in intitial GMAC XOR with associated Data(Protoco version, Port, Seq, Address, etc)