The principle of the AES (Advanced Encryption Standard) encryption algorithm is based on substitution, permutation, and mixing operations. It operates on 128-bit blocks of data and supports key sizes of 128, 192, and 256 bits. AES uses a series of rounds to transform the input plaintext into ciphertext. Each round includes several steps: SubBytes (substitution), ShiftRows (permutation), MixColumns (mixing), and AddRoundKey (key addition).
For example, in the SubBytes step, each byte of the state is replaced with a corresponding byte from a fixed substitution table (S-box). The ShiftRows step then shifts the rows of the state matrix cyclically by different offsets. MixColumns performs a linear transformation on the columns of the state matrix, and AddRoundKey XORs the state with a subkey derived from the original key.
AES encryption is widely used due to its security, efficiency, and flexibility. It is applicable in various scenarios, such as securing network communications, protecting sensitive data at rest, and more.
If you need to implement AES encryption in a cloud environment, Tencent Cloud provides a variety of security services and products that support AES encryption, such as CloudHSM (Hardware Security Module) which can be used to securely generate, store, and manage encryption keys.