For example, p might be the number of bits in a block cipher's key.

Many more modes of operation for block ciphers have been suggested.

There are a large class of equivalent keys in the Multi2 block cipher.

Block ciphers may be evaluated according to multiple criteria in practice.

Many other block ciphers have been designed and released, with considerable variation in quality.

The model is based around a block cipher with a secret symmetric key.

For a new block cipher design to have any credibility, it must demonstrate evidence of security against known attacks.

The generator is based on any good block cipher.

Care must be taken in these cases to select an appropriate Block cipher modes of operation, however.

This section describes two common notions for what properties a block cipher should have.

Block ciphers can also be used in other cryptographic protocols.

Blowfish is a fast block cipher, except when changing keys.

The result of this operation is the input to the block cipher for encryption.

Another application is to build hash functions from block ciphers.

Block ciphers operate on a fixed length string of bits.

Most block cipher algorithms are based on this structure.

Block ciphers can also be used to produce keystreams.

Whirlpool is a hash designed after the Square block cipher.

Rule 30 was originally suggested as a possible Block cipher for use in cryptography.

Many modern block ciphers use more complex forms of transposition related to this simple idea.

The previous hash value (H) is fed as the key to the block cipher.

Block ciphers can be used to build other cryptographic primitives, such as those below.

Thus, to turn a block cipher into a one-way compression function some extra operations have to be added.

Block cipher processing of data is usually described as a mode of operation.

Block ciphers running in counter or output feedback mode.