Cryptography

Question 0

IPsec

Answer 0

Only through IP networks

Provides integrity, confidentiality, SYSTEM authentication

Question 1

S-HTTP

Answer 1

Used to encrypt individual messages between two computers

Question 2

Zero Knowledge proof

Answer 2

Proving that you have a specific key without sharing that key or showing it to anyone

Question 3

Transposition cipher

Answer 3

Rearranging characters

Question 4

Substitution cipher

Answer 4

Exchanging characters

Question 5

DES

Answer 5

Algorithm: Data Encryption Algorithm (64bit)
(name changed from Lucifer (128bit))
Block cipher
Symmetric
64bit key (8 bit for parity, so true key is 56 bit)

Question 6

AES

Answer 6

Advanced Encryption Algorithm
Using rijndael algorithm
Used to bulk encrypt data
Symmetric

Question 7

PGP

Answer 7

Pretty good privacy

Hybrid symmetric/asymmetric free crypto system

Question 8

SET

Answer 8

Secure electronic transaction
Supposed to replace SSL
Developed by MasterCard and Visa
Too much overhead = not adopted

Question 9

Block cipher

Answer 9

Using substitution boxes (s-boxes) 
For bulk data
Fixed length grp of bits
Symmetric
Substitution and permutation
DES, AES, IDEA, RC5, BLOWFISH
ECB - electronic code book (encrypt CC numbers)
CBC - cipher block chaining (encrypt documents)
CFB - cipher feedback mode
OFB - output feedback
CTR - counter mode

Question 10

IDEA

Answer 10

128bit
Block cipher
64bit block, broken into 16subblocks and send trough 8 rounds of permutation
- meant to replace DES, but patented and requiring license fees

Question 11

Link encryption

Answer 11

Encrypts everything but data link messaging

Working in datalink and physical layer of OSI model

Question 12

HMAC

Answer 12

Massage authentication code
Symmetric key is added to the message and result put through hashing algorithm = MAC
- integrity
- system or data authentication

Question 13

CBC-MAC

Answer 13

Using block cipher to create MAC, which is the last block of cipher text
Only integrity

Question 14

RSA

Answer 14

Asymmetric
Data encryption, key exchange, digital signature
Rivest - Shamir - Adleman
- based on difficulty to factor large numbers into their original prime numbers

Question 15

Key clustering

Answer 15

Different keys generate the same cipher text from the same clear text

Question 16

Algorithm work factor

Answer 16

Amount of time and resource needed to break the encryption process or the crypto system