Security Plus Chapter 12

Front 1

What are the three core services offered by Cryptography?

Back 1

1. Encryption: converts text to cipher text and back.
   
2. Hashing:
   
3. Authentication:
   

Front 2

Name two common cipher types?

Back 2

1. Substitution: substitutes one character for another.
   
2. Transposition: Involves shifting characters a certain number of spaces
   

Front 3

Hashing is used to maintain what?

Back 3

the integrity of information

Front 4

Non-repudiation is the term used for?

Back 4

ensuring that senders cannot say they did not send a message

Front 5

Encryption involves both _____________ and ____________

Back 5

Algorithms and keys

Front 6

How is the algorithm and key used in encryption.

Back 6

1. Algorithms encrypt the clear text
   
2. Keys encrypt and decrypts the text
   

Front 7

The cryptography term Key Space means?

Back 7

How many bits are the encryption key.

Front 8

The cryptography term Work Factor means?

Back 8

Refers to a value indication the time it would take to break the encryption. The higher the value the more time it will take.

Front 9

The cryptography term One-Time Pads means?

Back 9

An encryption method that involves using a key only once.

Front 10

The cryptography term Block Ciphers vs. Stream Cipher mean?

Back 10

Stream encrypts data one bit at a time while a Block encrypts one block at a time.

Front 11

Block Ciphers vs. Stream Cipher what are the advantage of Stream over Block?

Back 11

Stream ciphers are less overhead, faster and less error prone a error in block ciphering renders the entire block useless.

Front 12

Stream Cipher vs. Block Ciphers what are the advantage of Block over Stream?

Back 12

Block ciphers are more secure

Front 13

The cryptography term Padding refers to?

Back 13

Adding zeros or ones to the end of a message to create an even number of blocks.

Front 14

The cryptography term XOR means?

Back 14

Means if one and only one the value is 1

Front 15

What is Symmetric encryption?

Back 15

The method uses the same key to encrypt and decrypt the message.

Front 16

What type of encryption is used on wireless networks?

Back 16

Symmetric encryption

Front 17

Name four other names for Symmetric encryption?

Back 17

1. Shared or pre-shared key
2. Secret key
3. Session key
4. Private key
   

Front 18

What is the advantage and disadvantages of Symmetric Encryption?

Back 18

Much faster than Asymmetric Encryption, the disadvantages are passing the encryption key and the number of key required to ensure confidentiality among all persons.

Front 19

How is the number of keys needed to encryption messages computed.

Back 19

Number of people X (Number of People -1)/2

Front 20

What is Data Encryption Standard (DES)?

Back 20

It is a deprecated 56-bit block Cipher that used to be the government standard, but it is no longer considered secure.

Front 21

Name four Data Encryption Standard (DES) based block ciphers used today?

Back 21

1. Blowfish which replace DES offers variable rates of encryption from 1 to 448 bits
2. Twofish offers 128-bit encryption
3. Triple DES (3DES) a DES base cipher that runs the information through three mathematical operations using three different keys 56-bit to 168-bit keys.
4. Rivest Cipher use the RC algorithm
   

Front 22

Rivest Cipher (RC4/RC5) are streaming block ciphers that use the RC algorithm. What are they used for?

Back 22

RC4/RC5 are stream cipher used in SSL and WEP (for wireless security)

Front 23

The Advanced Encryption Standard (AES) is a symmetric block cipher?

Back 23

AES replaced DES as the new standard for symmetric encryption. It supports 128-bit, 192-bit, and AES256 256-bit encryption.

Front 24

The Asymmetric encryption involves using two mathematically related keys to perform the ____________ and ______________ process

Back 24

Encryption and Decryption

Front 25

The two main concepts about Asymmetric encryption?

Back 25

1. Whatever operation one key in the pair does the other key undoes.
2. The two that are used a related but one cannot be derived from the other.
   

Front 26

Public and Private Keys are associated with which type of encryption?

Back 26

Asymmetric encryption

Front 27

How are the public and private keys use for encryption and decryption in Asymmetric encryption?

Back 27

The private key is used for decryption and the recipient's public key is used to encryption .

Front 28

Where do public key reside?

Back 28

Generally on a central server, but the idea is that whomever communicates with sender should have access to their public key.

Front 29

In order to ensure non-repudiation messages are _____________?

Back 29

Signed using the senders private key.

Front 30

What is the advantage and disadvantages of asymmetric Encryption?

Back 30

The public keys can securely be communicated to other parties unlike with symmetric encryption. Key management is a key benefit. Only one pair of keys per user is needed for encryption. A major disadvantage is speed.

Front 31

Name three Asymmetric Encryption Algorithms?

Back 31

1. Rivest Shamir Adleman (RSA): the first asymmetric algorithm tha implement signing and encryption.
2. Diffie-Hellman: is a secure key exchange protocol.
3. Elliptic curve: newer protocol based on Diffie-Hellman uses the DIgital Signature Algorithm (DSA) for signing messages.
   

Front 32

Quantum cryptography is used with fiber-optic networks. How does it work?

Back 32

Works by sending encrypted information as photons (particles of light) which is converted to binary data.

Front 33

What is the benefit of Quantum cryptography?

Back 33

1. Is that the state of the photons changes if passed through rogue networks.
2. The change is the state of the photons is easily detected indicating that the cryptography key should be changed.
   

Front 34

What is the difference between in-band key exchange and out-of-band key exchange.

Back 34

In the in-band key exchange the exchange is part of the communication. In out-band a separate channel is used to exchange keys.

Front 35

What is another name for hash value?

Back 35

Message Digest

Front 36

For the following four hashing algorithms what is the bit value of the generated hash:

1. Message Digest (MD2 - 5) most common
   
2. Secure Hash Algorithm (SHA0 - 2 1 common)
   
3. SHA-256 and 512
4. RACE integrity Primitive Evaluation Message Digest (RIPEMD)
   

Back 36

1. 128
2. 160
3. 256 and 512
4. Uses DES not secure
5. 128, 169, 256, and 320
   

Front 37

For the following four hashing algorithms do not generate hash values what do they use:

1. LANMAN (LM) (not secure)
   
2. NT LAN Manager (NLTM)
3. NTLMv2
   
4. Hash-based Message Authentication Code (HMAC)
   

Back 37

1. DES is used to encrypt the password
2. NTLM which uses MD4
3. Uses HMAC-MD5 to hash the challenge and response between client and server
4. Uses a secret key combined with the hashing algorithm to calculate the message authentication code (MAC). The MAC is the hash value.
   

Front 38

What is Trusted Platform Module (TPM)

Back 38

A computer chip on a system that is used to store the cryptographic keys used for encryption. BIOS must support TPM

Front 39

The secure replacements for:

1. HTTP
2. Secure Socket Layer (SSL)/Transport Layer Security (TLS)
3. FTP
4. Telnet
   

Back 39

1. HTTPS
2. TLS is more secure than SSL
3. Secure SFTP which rides on top of SSH
4. SSH
   

Front 40

The following secure protocols are used for encrypting:

1. Secure MIME (S/MIME)
2. Internet Protocol Security (IPSec)
3. Secure Copy Protocol (SCP)
4. WEP, WPA or WPA2 (most secure)
   

Back 40

1. Mail
2. All IP traffic
3. Runs on top of SSH encrypts the communication used to transfer a file.
4. Used encrypt wireless communication.
   

Front 41

Internet Protocol Security (IPSec) has two modes, what are they?

Back 41

1. Transport Mode only packet is encrypted
2. Tunnel Mode the header, packet and data are encrypted.
   

Front 42

Name three new security concepts for protecting keys?

Back 42

1. Ephemeral key uses a temporary key to encrypt a single message instead of a the same key for all messages.
2. Perfect forward secrecy a system that generates random public keys (ephemeral key) for each session.
   
3. Key stretching uses a special algorithm to convert weak passwords into a stronger key.
   

Front 43

PBKDF2 and Bcrypt are examples of what kind of key protection.

Back 43

Key stretching

Front 44

What is a Cipher suite?

Back 44

Cipher suite is a group of security algorithms used to provide authentication, encryption, and message authentication code functionally. Cipher suits are used to negotiate security settings in SSL and TLS.

Front 45

What are the two key negotiation protocols used by TLS?

Back 45

Diffie-Hellman Ephemeral (DHE) and Elliptic Curve Diffie-Hellman Ephemeral (ECDHE).

Front 46

Ephemeral key is key that?

Back 46

Uses a temporary key to encrypt a single message instead of the same key for all messages.

Front 47

Perfect forward secrecy is when?

Back 47

A system that generates random public keys (ephemeral key) for each session so that secret key exchange can occur during the communication.

Front 48

Key stretching uses a?

Back 48

Special algorithm to convert weak passwords into a stronger key.

Front 49

A Vigenere Cipher use a?

Back 49

Table to encrypt the message base on a intersection in the table.

Front 50

Key Space refers to what?

Back 50

How many bits are in the encryption key. The larger the key the more secure the key.

Front 51

Work Factor refers to what?

Back 51

A value indicating the time it would take to break the encryption.

Front 52

One-Time Pads refers to what?

Back 52

A very secure method of encryption information that involves using a key only once.

Front 53

Block Cipher vs. Stream Ciphers differences?

Back 53

Stream Cipher encrypt data one bit at a time, faster than block cipher, text is same size and part of the text can be invalid without invalidating all of it.

Block Cipher more secure, uses XOR , encrypt blocks