Chapter 1

Symmetric Key Cryptography

Classical ciphers and cryptanalysis

medium • 1 min read

Feistel networks and block cipher design principles

medium • 2 min read

Data Encryption Standard (DES) and AES algorithms

medium • 3 min read

Block cipher modes of operation (ECB, CBC, GCM)

medium • 4 min read

Stream ciphers and pseudo-random number generators

medium • 5 min read

Chapter 2

Public Key Cryptography

Number theory foundations (Modular arithmetic, Primes)

medium • 1 min read

RSA algorithm and its security properties

medium • 2 min read

Diffie-Hellman Key Exchange and Man-in-the-Middle

medium • 3 min read

Elliptic Curve Cryptography (ECC)

medium • 4 min read

ElGamal encryption scheme

medium • 5 min read

Chapter 3

Message Authentication and Hash Functions

Cryptographic hash functions (SHA-2, SHA-3)

medium • 1 min read

Message Authentication Codes (HMAC)

medium • 2 min read

Digital signatures (DSA, RSA signatures)

medium • 3 min read

Public Key Infrastructure (PKI) and X.509 certificates

medium • 4 min read

Key management and certificate revocation

medium • 5 min read

Chapter 4

Network Security Protocols

Transport Layer Security (TLS/SSL) handshakes

medium • 1 min read

IPSec architecture, ESP, and AH

medium • 2 min read

Secure Email (PGP, S/MIME)

medium • 3 min read

Authentication protocols (Kerberos, RADIUS)

medium • 4 min read

Secure Shell (SSH) and network access control

medium • 5 min read

Chapter 5

System Security and Modern Threats

Buffer overflows and memory corruption attacks

medium • 1 min read

Malware, ransomware, and botnets

medium • 2 min read

Web application security (XSS, SQL Injection, CSRF)

medium • 3 min read

Advanced Persistent Threats (APTs)

medium • 4 min read

Post-quantum cryptography overview

medium • 5 min read