1. Symmetric Cryptography
   1. Classical cryptosystem
      1. Substitution cipher
         1. Caesar cipher
         2. Monoalphabetic
         3. Polyalphabetic
            1. Vigenere cipher
            2. Vernam cipher
            3. Enigma cipher
         4. Playfair
         5. Hill cipher
         6. one time pad(OTP)
      2. Transposition cipher
         1. Rail fence
         2. Columnar transposition
         3. double transposition
         4. Route cipher
   2. Modern cryptosystem
      1. Stream cipher
         1. A 5/1
         2. A 5/2
         3. RC4
      2. Block cipher
         1. Algorithms
            1. RC2
            2. RC5
            3. RC6
            4. DES
            5. 3DES
            6. AES
         2. Modes
            1. ECB
            2. Electronic Codebook
            3. CBC
            4. Cipher Block Chaining
            5. CFB
            6. Cipher Feedback Mode
            7. OFB
            8. Output Feedback Mode
            9. CTR
            10. Counter iteration mode
2. services
   1. Confidentiality
   2. Intigrity
   3. Authentication
   4. Non-repudiation
   5. Key exchange
3. Asymmetric Cryptography
   1. Public key cryptosystems
      1. RSA
      2. Diffie-Hellman
      3. ECC
         1. elliptic curve cryptography
      4. DSA
      5. NTRU
   2. Hybrid encryption scheme
      1. ECIES
         1. ECC cryptography + KDF + Symmetric encryption algo. + MAC algo.
4. Hash Functions
   1. One way Hash functions
      1. Message Digest (MD)
         1. MD2
         2. MD4
         3. MD5
         4. MD6
      2. Secure Hash Algorithm (SHA)
         1. SHA-0
         2. SHA-1
         3. SHA-2
            1. SHA-2 family
            2. SHA-224
            3. SHA-256
            4. SHA-384
            5. SHA-512
         4. SHA-3
   2. RIPEMD (RACE Integrity Primitives Evaluation Message Digest)
      1. RIPEMD-128
      2. RIPEMD-160
      3. RIPEMD-256
      4. RIPEMD-320
5. Message Authentication Code (MAC)
   1. Algorithms
      1. HMAC
      2. CMAC
      3. KMAC
      4. GMAC
      5. Poly1305
      6. UMAC
      7. VMAC
   2. KDF (Key Derivation Function)
      1. PBKDF2
      2. Bcrypt
      3. Scrypt
      4. Argon2
   3. Randomness
      1. Secure random number generators
         1. PRNG
            1. Pseudo Random Number Genertators
         2. CSPRNG
            1. Cryptographic Secure Random Number Generators
6. PKI (Public Key Infrastructure)
   1. Infrastructure
      1. Decentralized PKI
      2. Blockchain-based PKI
   2. Components
      1. pub key certificate
      2. Private key tokens
      3. Certification authority
         1. Key functions
            1. Generating key pairs
            2. Issuing digital certificates
            3. Publishing Certificates
            4. Verifying Certificates
            5. Revocation of Certificates
      4. Registration authority
      5. certificate management system
   3. Digital signatures
      1. usage
         1. Sign messages
         2. Verify signatures
      2. schemes and algorithms
         1. RSA signatures
         2. ECDSA
         3. EIGamal signatures
7. Attacks & Cryptanalysis
   1. Common
      1. Known plaintext analysis(KPA)
      2. Chosen Plaintext Analysis(CPA)
      3. Ciphertext Only Attack (COA)
      4. Adaptive Chosen Plaintext(ACPA)
      5. Side channel Attack(SCA)
      6. Replay attack
      7. Timing Attacks
   2. Symmetric
      1. Brute Force Attack(BFA)
      2. Dictionary Attack
      3. MITM
      4. Linear Cryptanalysis
      5. Differential Cryptanalysis
   3. Hash systems
      1. Birthday attack
      2. Rainbow table