AES Basics and MATLAB Implementation

AES stands for Advanced Encryption Standard. It’s fundamentally an encryption-decryption algorithm used to secure data.

Encryption transforms raw input data into an unreadable format. Decryption reverses this process, turning the encrypted data back into its original form.

AES supports cryptographic keys of varying lengths: 128, 192, and 256 bits. These keys are used to encrypt and decrypt data in 128-bit blocks. The 128-bit AES algorithm is widely used to protect electronic transactions.

AES cores, designed by various companies, often contain both encryption and decryption modules that can run on a single core.

Typically, AES IP Cores support two modes: OFB (Output Feedback) and CTR (Counter) mode.

CTR (Counter) Mode

In CTR mode, the encryption process involves these steps:

1. The input to the encryption core is the output of a counter. An Initialization Vector (IV) is required to initialize the counter.
2. The input data is XORed with the output of the encryption module. The result of this XOR operation is the ciphertext, which is the encrypted data.

Decryption in CTR mode mirrors the encryption process:

1. The output of the counter (using the same IV as in encryption) is used as input.
2. The input data is then encrypted by XORing it with the output of the encryption core module. This results in the original, unencrypted data.

OFB (Output Feedback) Mode

In OFB mode, the output of the encryption operation is fed back as the input to the encryption core. An initialization vector is used for the first iteration.

The input data is encrypted by XORing it with the output of the encryption module.

Applications of AES

AES is widely used in a variety of applications, including:

• Wireless communication
• Electronic financial transactions
• Secure communications
• Secure video surveillance systems
• Encrypted data storage
• e-Business applications

Downloads

• Download AES MATLAB Code file
• Download DES MATLAB Code file