Information, Computer and Network Security Terms Glossary and Dictionary

CBC: Cipher Block Chaining

Cipher Block Chaining (CBC) is a mode of operation for a block cipher, one in which a sequence of bits is encrypted as a single unit or block with a cipher key applied to the entire block. Cipher block chaining uses what is known as an initialization vector (IV) of a certain length. CBC prevents the problems associated with Electronic Codebook (ECB), where every block of "plain text" maps to exactly one block of "cipher text" by having each encrypted block XORed with the previous block of ciphertext. In this way, identical patterns in different messages are encrypted differently, depending upon the difference in the previous data.

Related Terms

CBC: Cipher Block Chaining