A network stream needs to be encrypted. Sara, the network administrator, has selected a cipher which will encrypt 8 bits at a time before sending the data across the network. Which of the following has Sara selected?
A block cipher encrypts data into fixed-length groups of bits, called a block. In this question, the cipher is transmitting the data one block at a time.
In cryptography, a block cipher is a deterministic algorithm operating on fixed-length groups of bits, called a block, with an unvarying transformation that is specified by a symmetric key. Block ciphers operate as important elementary components in the design of many cryptographic protocols, and are widely used to implement encryption of bulk data.
The modern design of block ciphers is based on the concept of an iterated product cipher. In his seminal 1949 publication, Communication Theory …