20.4 Stream Ciphers & RC4 Flashcards
1
Q
What is a block cipher ?
A
Processes the input block of elements at a time, producing an output block for each input block.
2
Q
What does a stream cipher do?
A
Processes the input elements continuously, producing output one element at a time, as it goes along.
3
Q
What is RC4?
A
The most popular symmetric stream cipher.
4
Q
What does a typical stream cipher do?
A
Encrypts plaintext one byte at a time. Can do as little as one bit and larger than a byte.
5
Q
What is a pseudorandom stream?
A
One that is unpredictable without knowledge of the input key and that has an apparently random character.
6
Q
What is the output of the pseudorandom bit generator?
A
The key stream.
