A block scheme of this mode is presented in Fig. Due to obvious weaknesses, it is generally not recommended.

The ECB (Electronic Code Book) mode is the simplest of all. Now let’s introduce the five modes of AES. Or we can use the mode of AES which support a stream of plaintext, like CFB, OFB, CTR mode. We can use some algorithms for padding block when the plaintext is not enough a block, like PKCS5 or PKCS7, it also can defend against PA attack, if we use ECB or CBC mode. Block cipher algorithms should enable encryption of the plaintext with size which is different from the defined size of one block as well. Please note this, there is three length in the key, but the size of the encryption block always is 128 bits. The size of an AES block is 128 bits, whereas the size of the encryption key can be 128, 192 or 256 bits. It has been standardized by the NIST (National Institute of Standards and Technology) in 2001, in order to replace DES and 3DES which were used for encryption in that period. Today, AES (Advanced Encryption Standard) is one of the most used algorithms for block encryption.

The block ciphers are schemes for encryption or decryption where a block of plaintext is treated as a single block and is used to obtain a block of ciphertext with the same size. In this document, I will introduce the difference in the five kinds of mode. So I studied on the encryption algorithm. Recently, I did some work with Sawada-san on the TDE.

Block cipher decryption tool aes to cbc