Cryptographic Types

Question 1

Stream Cipher

Answer 1

Encrypts data bit by bit or byte by byte using a psuedo-random stream generated by a secret key

Question 2

Block Cipher

Answer 2

Symmetric encryption that encrypts data in fixed-size blocks, usually 64 or 128 bits, using a secret key

Question 3

AES

Answer 3

Can operate as a block cipher or a stream cipher (this is unique to AES)
128, 192, or 256 bit key sizes

Question 4

DES

Answer 4

One of the earliest encryption standards, 56-bt key to encrypt 64-bit data blocks
Short key length makes it vulnerable to brute force

Question 5

3DES

Answer 5

Applies the DES algorithm three times using three different keys, increasing the effective key length to 112 bits

Question 6

Blowfish and Twofish

Answer 6

Blowfish was known for speed and flexibility but prone to collision
Twofish is its successor, uses 128-bit blocks with key sizes up to 256 bits

Question 7

ChaCha20

Answer 7

Developed as a secure replacement for RC4
Popular in scenarios where low latency and strong security are required

Question 8

RSA

Answer 8

Asymmetric algorithm for both encryption and signatures
Relies on the difficulty of factoring large prime numbers

Question 9

DSA

Answer 9

Tailored solely for signing, focusing on proving that a message comes from a legitimate sender and has not been altered

Question 10

Diffie-Hellman

Answer 10

Allows two parties to establish a common symmetric key over an unsecured channel without exchanging that secure key

Question 11

ECC

Answer 11

Advanced form of encryption that uses the unique mathematical properites of elliptic curves to provide high security with smaller key sizes
256-bit key in ECC provides comparable security to a 3072-bit RSA key

Question 12

ECDSA

Answer 12

Uses elliptic curves to provide robust security without the heavy resource requirements of RSA or DSA

Question 13

ECDH

Answer 13

Elliptic Curve Diffie-Hellman
Uses elliptic curves to facilitate secure key exchanges