AES is the National Institute of Standards and Technology NIST designed to replace Des's 21st century Encryption standard. AES is a data block-based encryption method, that is, each processing of data is a piece (16 bytes), when the data is not a multiple of 16 bytes, this is called the Block cipher (different from the bit-based stream password), 16 bytes is the packet length. AES has a common ECB, CBC and other modes.
ECB: is a basic encryption method, ciphertext is divided into blocks of equal length of the block (not enough), and then individually encrypted, one by one output composed ciphertext.
Advantages: 1, simple, 2, in favor of parallel computing, 3, the error will not be transmitted;
Disadvantage: 1, can not hide the pattern of clear text, 2, may be active attack on the plaintext;
CBC: is a cyclic mode, the previous group of ciphertext and the current group of plaintext XOR or operation after encryption, the purpose of this is to enhance the difficulty of cracking.
Advantages: 1, not easy to actively attack, security better than ecb;2, suitable for transmitting long-length messages, SSL, IPSec standards.
Disadvantage: 1, not conducive to parallel computing, 2, error transmission, 3, the need to initialize the Vector IV.
The LKT4201N encryption chip supports AES-CBC, AES-ECB, AES-128, AES-192, AES-256, and international symmetric and asymmetric algorithms, and is a good choice for developers who need data encryption and decryption.
Brief introduction of AES algorithm features