WGU Into to Cryptography

Private key of the root CA

A business wants to use keys issued by a trusted third party to demonstrate to potential customers that it is a legitimate organization.Which key is used to sign the certificate issued to the business?

Public key of the company

A business wants to use keys issued by a trusted third party to demonstrate it is a legitimate organization to potential customers.Which key should the business send to potential customers to prove its identity?

Public Key Cryptography Standard (PKCS) #12

What should an administrator use to import and export all items written using X.509 that are part of a chain of trust?

Thumbprint

Which field displays the hash, or digest, of the certificate in an X.509 certificate?

Employee A's private key

Employee B sends Employee A an encrypted message.What does Employee A use to decrypt the message from Employee B?

AES

What is an example of a symmetric algorithm?

Cryptographic algorithm and Cryptographic key

Which two components involved in performing encryption are known to the party that will perform decryption before symmetric encryption is applied?Choose 2 answers.

Employee B's public key

Employee A created a secret key and wants to send it to Employee B without any coworkers being able to decrypt the message.Which key needs to encrypt the message?

ECB

Which mode encrypts each group with the same key, leaving each group independent of the others?

Electronic Code Book (ECB)

Which mode of block encryption results in the same outcome for matching blocks of a plaintext message?

Uses an initialization vector (IV) to encrypt the first block, then uses the result of the encryption to encrypt the next block

How does CBC mode encryption function?

ECB

Which encryption mode always produces the same result for the same plaintext?

Skipjack

Which information protection method has an 80-bit key and operates on 64-bit data blocks?

12

How many transformation rounds does AES use with a 192-bit key?

10

How many transformation rounds does AES use with a 128-bit key?

AES

Which encryption algorithm did the National Institute of Standards and Technology (NIST) designate as a specification for the encryption of electronic information?

The entire hash is different.

What happens to the hash of a file if it is rehashed after the first character of the file is changed?

128

What is the length (in bits) of an MD5 hash output?

14

How many characters are used in an LM hash password?

NTLM

A Windows credential is identified as follows: user:FDA95FBABC199D22LLD3B435B51876KK:199DDFD4EF0E9CD9KMNC6FE771IL124B8:::What is used to store this password?

Precompiled list of hash values

What is a rainbow table?

Stream

Which type of cipher is ChaCha?

40 bits

What is the key size for RC4 with WEP?

DES

Which symmetric encryption technique uses a 56-bit key size and a 64-bit block size?

WPA

Which wireless security standard uses a 128-bit RC4 stream cipher for encrypted communications?

Symmetric

A security analyst decrypted a data set with the same key that originally encrypted the data set.Which cryptographic operation did the analyst use?

Symmetric block

What should be used when large amounts of data need to be encrypted and decrypted for secure storage based on groupings of 128, 192, or 256 bits?

It uses the same key to encrypt and decrypt large amounts of media.

Why is symmetric stream used to encrypt video when speed is a major concern?

It encrypts a small amount of information, which is decrypted with the corresponding private key.

Why should an asymmetric public key be used to encrypt a symmetric key that is being sent to one person?

Man-in-the-middle

Which type of attacks are Diffie-Hellman methods vulnerable to?

Output feedback (OFB) loop

Which mechanism mitigates a copy-and-paste attack when using AES?

ECDH

Which mechanism can be used to ensure perfect forward secrecy during key exchange when using symmetric encryption?

Forward secrecy

Which encryption component ensures that the compromise of a long-term key prevents the compromise of any previous session keys?

Distributed peer-to-peer network

How is information about Bitcoin transactions stored?

Adding blocks to a blockchain is computationally expensive.

What is one of the primary characteristics of a blockchain in the context of Bitcoin?

256

What is the length (in bits) of the private key used to sign transactions and associated with an individual wallet in the context of Bitcoin?

Only has factors of itself and 1

What defines a prime number?

5

What is 29 mod 12?

Initialization vector

What can XOR use as a pseudorandom number to create unique ciphertext?

Uses the results of the IV to encrypt the next block

How does cipher block chaining (CBC) create randomness in a second block after encrypting the first block with an initialization vector (IV)?

Issued

Which certificate management process involves key recovery?

Signing it with its private key

Which task does a root CA perform before publishing its own certificate?

SHA-1

Which algorithm is used to generate the thumbprint of a certificate?

Encrypt by using symmetric keys and distribute by using asymmetric keys

Large volumes of plaintext need to be encrypted, and the encryption keys need to be securely distributed.Which approach should be used for encryption and distribution?

A public key is used for encryption, and a private key is used for decryption.

What is the role of a key in asymmetric encryption and decryption?

Digital signature

A security analyst is validating the integrity and authenticity of a data transaction.Which PKI component is being used?

Certificate authority (CA)

Which PKI component generates digital certificates?

40

What is the maximum length (in bits) of encryption keys used by the WEP protocol?

Support for an authentication server

What is a difference between WPA-Enterprise and WPA-Personal?

RC4

Which cipher is used with WEP?

Hashes the initialization vector and secret key

How does TKIP improve WPA over WEP?

At the headquarters and the offsite location

An administrator has configured a virtual private network (VPN) connection utilizing IPsec tunnel mode with Encapsulating Security Payload (ESP) between the corporate office and a remote office.Where can the packets be inspected by intrusion detection systems (IDSs) and virus scanners?

UDP 500

Which default port must be open for the IPsec key exchange to be successful?

51

Which protocol indicates the virtual private network (VPN) is using Authentication Header (AH)?

Bifid

Which cipher uses a grid to map letters into numeric values?

Playfair

Which cipher uses a five-by-five matrix with nonrepeating characters?

Analyzing ciphertext to identify text variation and comparing the text to standard English characters

What does a frequency analysis attack to break encryption involve?

Kasiski examination

Which technique should a security analyst use to determine the key length in a Vigenère cipher?

Brute-force

Which attack tries every combination of letters, numbers, and special characters?

Takes a list of the most common words and tries each entry

How does a dictionary attack break a cipher?