What Is AES (Advanced Encryption Standard)?

A quick description of the AES (Advanced Encryption Standard) cipher is provided. AES is based on the Rijndael cipher and uses a substitution-permutation network, not a Feistel network. AES is more secure and faster than DES.

What Is AES (Advanced Encryption Standard)? The AES (Advanced Encryption Standard) is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) in 2001, see the FIPS PUB 197 (Federal Information Processing Standards Publication 197): "Announcing the ADVANCED ENCRYPTION STANDARD (AES)".

AES has been adopted by the US government and is now used worldwide. It supersedes the Data Encryption Standard (DES), which was published in 1977 by the US government in FIPS PUB 46.

AES is based on the Rijndael cipher developed by two Belgian cryptographers, Joan Daemen and Vincent Rijmen, who submitted a proposal to NIST during the AES selection process. Rijndael cipher is a family of ciphers with different key and block sizes. But AES only selected 3 ciphers with 1 block size of 128 bits and 3 key lengths: 128, 192 and 256 bits:

Unlike its predecessor DES (Data Encryption Standard), AES (or Rijndael) cipher uses a substitution-permutation network, not a Feistel network, see the next tutorial for more details.

Comparing to DES, AES is more secure and faster.

Last update: 2015.

Table of Contents

 About This Book

 Cryptography Terminology

 Cryptography Basic Concepts

Introduction to AES (Advanced Encryption Standard)

What Is AES (Advanced Encryption Standard)?

 AES, or Rijndael, Encryption Algorithm

 AES Key Schedule Algorithm

 AES Key Schedule Example

 AES MixColumns() Procedure Algorithm

 Example Vector of AES Encryption

 AES Standard Decryption Algorithm

 AES Equivalent Decryption Algorithm

 Introduction to DES Algorithm

 DES Algorithm - Illustrated with Java Programs

 DES Algorithm Java Implementation

 DES Algorithm - Java Implementation in JDK JCE

 DES Encryption Operation Modes

 DES in Stream Cipher Modes

 PHP Implementation of DES - mcrypt

 Blowfish - 8-Byte Block Cipher

 Secret Key Generation and Management

 Cipher - Secret Key Encryption and Decryption

 Introduction of RSA Algorithm

 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

 MD5 Mesasge Digest Algorithm

 SHA1 Mesasge Digest Algorithm

 OpenSSL Introduction and Installation

 OpenSSL Generating and Managing RSA Keys

 OpenSSL Managing Certificates

 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"

 Using Certificates in IE (Internet Explorer)

 Using Certificates in Firefox

 Using Certificates in Google Chrome

 Outdated Tutorials

 References

 PDF Printing Version