RSA Security 5.2.2 manual 3Electronic Codebook ECB Mode

Cryptography Overview

Electronic Codebook (ECB) Mode

ECB is not a feedback mode; it encrypts each block of input independently of all other blocks. Plaintext patterns are not concealed; instead each identical block of plaintext yields an identical block of ciphertext. This could help an eavesdropper break the code. In addition, the plaintext can be easily manipulated by removing, repeating, or interchanging blocks. The speed of each encryption operation is identical to that of the block cipher. ECB mode is as secure as the underlying block cipher.

1st message

block

2nd message

block

Block Cipher

Key (K)

Block Cipher

1st cipher

block

2nd cipher

block

Key (K)

Figure 3-3Electronic Codebook (ECB) Mode

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