Symmetric Algorithms 6.2

Question 1

Data Encryption Standard (DES)

Answer 1

DES and Triple DES. 64-bit block cipher. 56-bit key which is small in modern terms. It is easily brute-forced with today’s technology.

Question 2

Triple DES (3DES)

Answer 2

Three different keys; is the strongest 3DES encryption method. Two separate keys is deprecated. A single key isn’t allowed. K1 Encrypts, K2 Decrypts (its not the same key as K1 so its jumbles more), K3 Encrypts again.
Superseded by Advanced Encryption Standard (AES)

Question 3

Rivest Cipher 4 (RC4)

Answer 3

Made by Ron Rivest, most used stream cipher. It was also a part of SSL, but it was removed when SSL evolved into TLS.

Question 4

Advanced Encryption Standard (AES)

Answer 4

Most popular encryption today. Uses a 128-bit block cipher. It supports 128, 192, and 256-bit key sizes. It is used in WPA2 for wireless encryption.

Question 5

Federal Information Processing Standards (FIPS)

Answer 5

FIPS are standards and guidelines for federal computer systems that are developed by National Institute of Standards and Technology (NIST) in accordance with the Federal Information Security Management Act (FISMA)

Question 6

Blowfish

Answer 6

Blowfish created in 1994. Uses a 64-bit block cipher and variable length key (32-448 bits). There is no known way to break the full 16 rounds of encryption.

Question 7

Twofish

Answer 7

The successor to Blowfish. 128-bit block cipher, key sizes up to 256. No patent, public domain.