**Cryptography Tutorials - Herong's Tutorial Examples** - v5.42, by Herong Yang

What Is Cryptography?

This section describes what is cryptography - The study of techniques related to all aspects of data security.

**Cryptography** - The study of techniques related to all aspects of data security.
The word "cryptography" is derived from the ancient Greek words "kryptos" (hidden)
and "graphia" (writing).

Some aspects of data security:

- Confidentiality - Keeping data secret.
- Data Integrity - Ensuring data has not been altered.
- Entity Authentication - Identifying parties involved.
- Data Origin Authentication - Identifying the data origin.

**Cryptanalysis**
- The study of techniques to defeat cryptographic techniques.

Table of Contents

Introduction to AES (Advanced Encryption Standard)

DES Algorithm - Illustrated with Java Programs

DES Algorithm Java Implementation

DES Algorithm - Java Implementation in JDK JCE

DES Encryption Operation Modes

PHP Implementation of DES - mcrypt

Blowfish - 8-Byte Block Cipher

Secret Key Generation and Management

Cipher - Secret Key Encryption and Decryption

RSA Implementation using java.math.BigInteger Class

Introduction of DSA (Digital Signature Algorithm)

Java Default Implementation of DSA

Private key and Public Key Pair Generation

PKCS#8/X.509 Private/Public Encoding Standards

Cipher - Public Key Encryption and Decryption

OpenSSL Introduction and Installation

OpenSSL Generating and Managing RSA Keys

OpenSSL Generating and Signing CSR

OpenSSL Validating Certificate Path

"keytool" and "keystore" from JDK

"OpenSSL" Signing CSR Generated by "keytool"

Migrating Keys from "keystore" to "OpenSSL" Key Files

Certificate X.509 Standard and DER/PEM Formats

Migrating Keys from "OpenSSL" Key Files to "keystore"