2.8 Algorithms, Protocols, Encryptions

Question 1

AES

Answer 1

Advanced Encryption Standard

Gold standard for encryption

Symmetric Key Block Cipher
Data Block size: 128-bit blocks
Key size: 128, 192, 256

Used in WPA2

AES-256: Considered to be the most secure encryption algorithm available today

• Government computer security
• Cybersecurity
• Electronic data protection
• Wireless security
• Processor security
• File encryption
• SSL/TLS

Question 2

Blowfish

Answer 2

Symmetric Key Block Cipher
Data Block size: 64-bit blocks
Key size: 32 to 448

Free and open source
Faster than AES with smaller blocks

AES is more secure

Question 3

RSA

Answer 3

Asymmetric Key Block Cipher

Widely used, slow, highly effective

• Secure messages before you send them
• Certify your notes so recipients know they haven’t been altered
• Slow data transfer rate
• Cannot be used for public data encryption
• Decryption requires intensive processing on the receiver’s end

Question 4

RC4

Answer 4

Rivest Cipher 4
Symmetric Key Stream Cipher

Deprecated for vulnerability

used for simplicity and speed

It is generally used in applications such as Secure Socket Layer (SSL), Transport Layer Security (TLS), and also used in IEEE 802.11 wireless LAN

Question 5

MD5

Answer 5

HASHING

message-digest hashing function

a cryptographic protocol that verifies messages, content, and digital signatures. It’s a one-way function that takes a message of any length and returns a fixed-length digest value. The digest value is represented as a 32-digit hexadecimal number.

it’s easy to generate MD5 collisions, superseded by other hash functions

Question 6

DES

Answer 6

Data Encryption Standard

Became vulnerable to brute force attacks, retired in 2005

Symmetric Key Block Cipher

Data Block size: 64-bit
Key size: 56

Question 7

3DES

Answer 7

Symmetric key block cipher

Data Block size: 64-bit
Key size: 56, 112, 168

applies the DES algorithm three times to each data block

reaching EOL and will be deprecated after 2023

Question 8

SHA-2

Answer 8

Secure Hash Algorithm v2

SHA-256 is the most common implementation from this standard.

Use: password hashing algorithm function used in -
* TLS and SSL
* SSH
* S/MIME
* IPsec
* SNMPv3

Question 9

Diffie-Hellman

Answer 9

Key Exchange

allows two parties to securely exchange asymmetric keys over a public channel.

Question 10

ESP

Answer 10

Encapsulating Security Payload

Protocol in the Internet Protocol Security (IPsec) set

ESP encrypts and authenticates data packets sent between computers using a Virtual Private Network (VPN).

Question 11

AH

Answer 11

Authentication Header
hashing algorithm
hashes the packet data for additional data integrity

Question 12

MS-CHAP

Answer 12

Microsoft Challenge Handshake Authentication Protocol

Security issues related to the use of DES (Data Encryption Standard) encryption in MS CHAP eliminate it from consideration for modern authentication.

Question 13

ECC

Answer 13

Elliptic Curve Cryptography

Good encryption for mobile devices

smaller storage and transmission requirements

uses public and private keys

Question 14

PGP

Answer 14

Pretty Good Privacy

• Encrypts and decrypts messages
• Authenticates messages using digital signatures
• Encrypts files
• Verifies various file types, including emails, files, directories, and disk partitions

Question 15

SAE

Answer 15

Simultaneous Authentication of Equals

used in WPA3

protects against brute force and dictionary attacks

Question 16

EAP

Answer 16

Extensible Authentication Protocol

supports multiple authentication methods

used primarily for wireless LANS

Question 17

EAP-FAST

Answer 17

EAP-FAST stands for Flexible Authentication through Secure Tunneling. It is an authentication method for wireless networks that uses Transport Layer Security (TLS) to establish a secure tunnel between a peer and a server.

Question 18

EAP-TLS

Answer 18

Extensible Authentication Protocol–Transport Layer Security (EAP-TLS) is an open standard that provides network security through digital authentication. It’s the most commonly used authentication protocol on WPA2-Enterprise networks

Question 19

EAP-TTLS

Answer 19

EAP Tunneled Transport Layer Security (EAP-TTLS) is an EAP protocol that extends TLS.

Question 20

EAP-PEAP

Answer 20

EAP- Protected Extensible Authentication Protocol (EAP-PEAP) is a protocol that creates an encrypted channel before password-based authentication.

Question 21

Hashing algorithms

Answer 21

MD5 - common, least secure
SHA-1 - 160 bit hash
SHA-2 - 256 bit hash, used in block chain, well known
RIPEMD-320 - longer hash strings