Fundamental Information Security Chapter 9: Cryptography
Bob received a message from Alice that contains a digital signature. What cryptographic key does Bob use to verify the digital signature? Answers: Alice's public key Alice's private key Bob's public key Bob's private key
Alice's public key
Which information security objective allows trusted entities to endorse information? Answers: Validation Authorization Certification Witnessing
Certification
Betty receives a cipher text message from her colleague Tim. What type of function does Betty need to use to read the plaintext message? Answers: Encryption Hashing Decryption Validation
Decryption
What mathematical problem forms the basis of most modern cryptographic algorithms? answers: Factoring large primes Traveling salesman problem Quantum mechanics Birthday problem
Factoring large primes
Gary is sending a message to Patricia. He wants to ensure that nobody tampers with the message while it is in transit. What goal of cryptography is Gary attempting to achieve? answers: Confidentiality Integrity Authentication Nonrepudiation
Integrity
What is NOT a symmetric encryption algorithm? Rivest-Shamir-Adelman (RSA) Data Encryption Standard (DES) International Data Encryption Algorithm (IDEA) Carlisle Adams Stafford Tavares (CAST)
Rivest-Shamir-Adelman (RSA)
What is NOT an effective key distribution method for plaintext encryption keys? Answers: Paper Unencrypted email CD Smart card
Unencrypted email
What standard is NOT secure and should never be used on modern wireless networks? Answers: Wired Equivalent Privacy (WEP) Wi-Fi Protected Access (WPA) Wi-Fi Protected Access version 2 (WPA2) 802.11ac
Wired Equivalent Privacy (WEP)
A keyword mixed alphabet cipher uses a cipher alphabet that consists of a keyword, minus duplicates, followed by the remaining letters of the alphabet true or false
true
A person demonstrates anonymity when posting information to a web discussion site without authorities knowing who he or she is. Answers: true or false
true
A salt value is a set of random characters you can combine with an actual input key to create the encryption key. Answers: true or false
true
Digital signatures require asymmetric key cryptography. Answers: true or false
true
Digital signatures require asymmetric key cryptography. true or false
true
The Diffie-Hellman (DHE) algorithm is the basis for several common key exchange protocols, including Diffie-Hellman in Ephemeral mode (DHE) and Elliptic Curve DHE (ECDHE). Answers: true or false
true
The hash message authentication code (HMAC) is a hash function that uses a key to create a hash, or message digest. true or false
true
In a chosen-ciphertext attack, cryptanalysts submit data coded with the same cipher and key they are trying to break to the decryption device to see either the plaintext output or the effect the decrypted message has on some system. true or false?
true
A private key cipher is also called an asymmetric key cipher. true or false
false
Cryptographic key distribution is typically done by phone. Answers: true or false
false
Product cipher is an encryption algorithm that has no corresponding decryption algorithm. Answers: true or false
false
The term certificate authority (CA) refers to a trusted repository of all public keys. Answers: true or false
false
Which cryptographic attack offers cryptanalysts the most information about how an encryption algorithm works? Answers: Chosen plaintext Ciphertext only Known plaintext Chosen ciphertext
Chosen plaintext
When Patricia receives a message from Gary, she wants to be able to demonstrate to Sue that the message actually came from Gary. What goal of cryptography is Patricia attempting to achieve? Answers: Confidentiality Integrity Authentication Nonrepudiation
Nonrepudiation
Which of the following allows a certificate authority (CA) to revoke a compromised digital certificate in real time? Answers: Certificate revocation list (CRL)International Data Encryption Algorithm (IDEA) Transport Layer Security (TLS) Online Certificate Status Protocol (OCSP)
Online Certificate Status Protocol (OCSP)
The financial industry created the ANSI X9.17 standard to define key management procedures. true or false
true
Which set of characteristics describes the Caesar cipher accurately? answers: Asymmetric, block, substitution Asymmetric, stream, transposition Symmetric, stream, substitution Symmetric, block, transposition
Symmetric, stream, substitution
Message authentication confirms the identity of the person who started a correspondence. Answers: true or false
true
Alice would like to send a message to Bob securely and wishes to encrypt the contents of the message. What key does she use to encrypt this message? Answers: Alice's public key Alice's private key Bob's public key Bob's private key
Bob's public key
Which approach to cryptography provides the strongest theoretical protection? Answers: Quantum cryptography Asymmetric cryptography Elliptic curve cryptography Classic cryptography
Quantum cryptography
You must always use the same algorithm to encrypt information and decrypt the same information. Answers: true or false
false
A digitized signature is a combination of a strong hash of a message and a secret key. Answers: true or false
false