COMPUTER FUNDAMENTALS

Detailed explanation-1: -A stream cipher is an encryption algorithm that encrypts 1 bit or byte of plaintext at a time. It uses an infinite stream of pseudorandom bits as the key.

Detailed explanation-2: -Substitution ciphers. A single alphabet is used to encrypt the entire plaintext message. For example, if the letter A is enciphered as the letter K, this will be the same for the entire message. A more complex substitution using a mixed alphabet to encrypt each bit, character or character block of a plaintext message.

Detailed explanation-3: -AES-128 uses a 128-bit key length to encrypt and decrypt a block of messages. AES-192 uses a 192-bit key length to encrypt and decrypt a block of messages.

Detailed explanation-4: -A block cipher is a method of encrypting data in blocks to produce ciphertext using a cryptographic key and algorithm. The block cipher processes fixed-size blocks simultaneously, as opposed to a stream cipher, which encrypts data one bit at a time.

Detailed explanation-5: -In cryptography, a block cipher is a deterministic algorithm operating on fixed-length groups of bits, called blocks. Block ciphers are specified elementary components in the design of many cryptographic protocols and are widely used to encrypt large amounts of data, including in data exchange protocols.