Cryptography Flashcards
(77 cards)
1
Q
Making something less visible or obvious
ex:making a picture blurry
A
Diffusion
2
Q
CRL
A
Certification Revocation List
-Being replaced by OCSP because of speed
3
Q
DES - first type of block encryption
A
Data Encryption Standard
4
Q
Taking one value and changing it for another
ex:making all A’s into C’s
A
Subsitution
5
Q
Data at rest
A
Something stored and not being used - something sitting on a hard drive or flash drive
6
Q
Cryptanalysis
A
Breaking encrypted codes
7
Q
Type of key that can only encrypt
A
Public Key
8
Q
Unlike block ciphers, this one works by encrypting one bit at a time as it passes through
A
Streaming Ciphers
9
Q
Cipher that works like a decoder ring
A
Ceaser Cipher
10
Q
Which is older?
MD5 or SHA-1
A
MD5
11
Q
Shared key for a set of data
A
Session Key
12
Q
Type of key that can decrpt
A
Private Key
13
Q
Ripemd
Bit #
A
Not very common Hash
128, 160, 256, 320 bit hash
14
Q
HMAC
A
Hash-based message authentication code
- requires each side of the conversation to have the same key
- provides message integrity
- based on standard hashes
15
Q
ECB
A
Electronic Code Book
16
Q
GCM
- block encryption with authentication
- commonly used in packetized data
A
Galois Counter Mode
17
Q
Encryption/Decryption
A
Hiding data and then bringing it back
18
Q
AES
A
Advanced Encryption System
19
Q
EDH or DHE
A
Ephemeral Diffie Hellman
20
Q
Type of encryption used for WPA2
A
AES
21
Q
In-band
A
Key is sent with encrypted data
22
Q
Mixing something up
ex:moving pixels around in a picture
A
Confusion
23
Q
PKCS-7
A
Is a way to store certificates as individual files
24
Q
Key Stretching
A
Stretches out the password/hash
ex: bcrypt
25
Digital Signature
Just a hash of whatever data you're looking at
26
Attack using a pre-generated index hash table for harder passwords/hashes than brute force can handle
Rainbow Table Attack
27
What are the 4 types of Symmetric Block Modes
Cipher Block Chaining (CBC)
Cipher Feedback (CFB)
Output Feedback (OFB)
Counter (CTR)
28
Type of Streaming Cipher
RC4
29
MD5
| Bit #
Message Digest 5
| 128 bit
30
RSA Cryptosystems
Asymmetric Algorithm
31
TLS
| -provides transport encryption
Transport Layer Security
32
Temporary key so it can't be used in future sessions
| -provides "perfect forward secrecy"
Ephemeral Key
33
PGP
Pretty Good Privacy
| Asymmetric encryption originally used for email
34
Cipher that uses a grid setup like a ceaser cipher but uses a key that's applied instead of ROT telling you how far to turn
Vigenere Cipher
35
ECDHE
Elliptic Curve Diffie Hellman Ephermeral
36
Encrypts data in small chucks until finished
Block Encryption
37
Block cipher
64-bit block size
16 rounds
Key size: 32-448 bits
Blowfish
38
Data in transit
Data that is being transferred like over the internet
39
Streaming cipher
1 bit at a time
1 rounds
Key size: 40 - 2048 bit
RC4
40
What is Cain and Abel
A password/hash cracking program
41
Salt
Adding characters to a password before hashing to make password very hard to crack
42
- Block modes will always generate same results with same input
- Can generate patterns that give away data
- No one uses this anymore
ECB - Electronic Code Book
43
Symmetric Block Mode
| -Uses Initialization Vector to XOR to encrypt
CBC - Cipher Block Chaining
44
Symmetric Block Modes use this to ensure the output block is uniquely different?
IV - Initialization Vectors
45
Encryption style that uses the same key to encrypt and decrypt
Symmetric encryption
46
Out-of-band
Delivering the key separately from data
47
SHA 1 and 2
| Bit #
```
Secure Hash Algorithm
SHA-1
160 bit
SHA-2
256bit and 512bit
```
48
Block cipher
64-bit block size
16 rounds
Key size: 56 bit
DES - Data Encryption Standard
49
PKI
```
Public Key Infrastructure
Is a hierarchy
Certificate Authorities at top
Intermediate Authorities
Then Users at the bottom
```
50
What kind of encryption do computers use?
Binary Encryption
51
IPsec
Internet Protocol Security
52
Digital Certificate
Includes public key/digital signature/3rd party digital signature
This is what a website will send you so you know they are legit
53
Type of encryption used for WPA
RC4
54
Block cipher
128-bit block size
10, 12, or 14 rounds
Key size: 128, 192, or 256 bit
AES - Advanced Encryption System
55
Data in process
Data that is being used and is on memory(ram) or the CPU
56
Diffie-Hellman
Asymmetric algorithm
| Key exchange protocol
57
Symmetric Block Mode
| -Uses Initialization Vector to encrypt to XOR to replace IV with output
CFB - Cipher Feedback
58
Symmetric block encryption
| Still used by Gov't
AES - Advanced Encryption System
59
PFS
| -all browsers now-a-days have to support this
Perfect Forward Secrecy
60
OCSP
Online Certificate Status Protocol
| -Is a more modern version of Certification Revocation List (CRL)
61
Steganography
- Hides data within data
- Commonly used with graphic images
- Hidden data may or may not be encrypted
62
Types of Hashes
MD5
SHA
SHA-2 (Most common)
Ripemd (not very common)
63
Hashes
- Create a small value from any amount of data
| - Will produce the same results each time the source is hashed
64
Block cipher
64-bit block size
16 rounds
Key size: 56 bit x3
3DES
| Triple DES
65
Practice of disguising information in a way that looks random
Cryptography
66
Symmetric Block Mode
| -Uses Initialization Vector to encrypt to XOR
OFB - Output Feedback
67
PKCS-12
Stores certificates and private keys as a package
68
Uses a key pair - public and private key
-public key is only used to encrypt
-private key is only used to decrypt
Used mostly to change a session key securely
Asymmetric Encryption
69
Unsigned Certificate
Can be made easily - they just don't have the 3rd party vouching for them
70
Principle that states as long as you don't know what the key is, you can understand the algorithm completely and still not be able to crack it
Kerckhoffs's Principle
71
ECC
| Creates a smaller key than RSA with the same security
Elliptic Curve Cryptography
72
Taking something that looks like it makes sense and to hide it so it doesn't make sense to the outside observer
Obfuscation
73
Example of ROT2
Turning a decoder ring twice
74
Web of Trust
Uses a web of mutually trusting peers and requires a lot of maintenance
75
Symmetric Block Mode
- Uses NONCE to Counter Value to Encrypt first block to XOR
- Counter then gets incremented each round
CTR - Counter
76
Defined piece of cryptography process that programmers can use to get stuff done - defines key properties, communication requirements for the key exchange and the actions taken through encryption and decryption process
Cryptosystem
77
Primary way we encrypt data
Symmetric Encryption
