Cipher Block Chaining

What Does Cipher Block Chaining Mean?

In a cipher block chaining process, data is encrypted in
specific blocks, and each block is dependent on the blocks before it for
decryption. The process uses something called an initialization vector to help
tie these blocks of encrypted data together.


Techopedia Explains Cipher Block Chaining

Invented in 1976, cipher block chaining provides a consistent way to encrypt and decrypt large amounts of data. In a block cipher process, text blocks are treated as isolated units to be encrypted and decrypted sequentially. An alternative is a stream cipher method, where each bit gets acted on independently.

In cipher block chaining, each cipher text block is decrypted in a process that requires observing the blocks that have already been processed. The cipher block chaining process uses a logical gate called XOR to administer this process of observation.

Cipher block chaining is often suggested as a stronger method of decryption, ensuring quality. However, some experts warn against certain vulnerabilities of cipher block chaining, including the use of predictable initialization vectors.


Related Terms

Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…