Advanced Encryption Standard (AES)

Advanced Encryption Standard (AES), originally known as ‘Rijndael’, is a widely used encryption algorithm designed to secure sensitive data. Developed by Vincent Rijmen and Joan Daemen, it was later approved as a federal encryption standard in the United States in 2001.

Rijndael is a family of ciphers with a block size of 12 bits, but with three different key lengths: 128, 192, and 256 bits. Each key length corresponds to a different number of encryption rounds (10, 12, and 14). The AES algorithm involves multiple rounds of processing, including substitution (SubBytes), permutation (ShiftRows), mixing (MixColumns), and adding round keys. Each round transforms the plaintext into ciphertext, making it difficult to reverse-engineer without the correct key.

The AES algorithm is a symmetric-key algorithm (the same key is used for both encrypting and decrypting the data), and is considered a solid and secure cipher due to its large key sizes and the complexity of its encryption process.

It is resistant to various cryptographic attacks, including brute-force attacks. The algorithm has been extensively analysed and is used globally for securing sensitive information. Additionally, AES is efficient in both software and hardware implementations, making it suitable for a wide range of devices and applications.