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created at 2021-05-11

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)

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OFB(Output FeedBack)

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CTR(CounTeR)

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Galois Counter Mode

produce Tag(MAC) and CT

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with AEAD(Authentication Encryption with Associated Data)

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

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