CCNA Security - Chapter 7 Exam Answers Download PDF Test Online

CCNA Security Chapter 7 Exam Answers

1. What is the focus of cryptanalysis?
   • hiding secret codes
   • developing secret codes
   • breaking encrypted codes
   • implementing encrypted codes
2. How many bits does the Data Encryption Standard (DES) use for data encryption?
   • 40 bits
   • 56 bits
   • 64 bits
   • 72 bits
3. Which statement describes the Software-Optimized Encryption Algorithm (SEAL)?
   • SEAL is a stream cipher.
   • It uses a 112-bit encryption key.
   • It is an example of an asymmetric algorithm.
   • It requires more CPU resources than software-based AES does.
4. Which encryption algorithm is an asymmetric algorithm?
   • DH
   • SEAL
   • 3DES
   • AES
5. An online retailer needs a service to support the nonrepudiation of the transaction. Which component is used for this service?
   • the private key of the retailer
   • the unique shared secret known only by the retailer and the customer
   • the public key of the retailer
   • the digital signatures
6. In which situation is an asymmetric key algorithm used?
   • Two Cisco routers authenticate each other with CHAP.
   • User data is transmitted across the network after a VPN is established.
   • An office manager encrypts confidential files before saving them to a removable device.
   • A network administrator connects to a Cisco router with SSH.
7. What is the purpose of a nonrepudiation service in secure communications?
   • to ensure that encrypted secure communications cannot be decoded
   • to confirm the identity of the recipient of the communications
   • to provide the highest encryption level possible
   • to ensure that the source of the communications is confirmed
8. Which objective of secure communications is achieved by encrypting data?
   • integrity
   • authentication
   • confidentiality
   • availability
9. Why is the 3DES algorithm often preferred over the AES algorithm?
   • 3DES is more trusted because it has been proven secure for a longer period than AES.
   • AES is more expensive to implement than 3DES.
   • 3DES performs better in high-throughput, low-latency environments than AES.
   • Major networking equipment vendors such as Cisco have not yet adopted AES.
10. What is the most common use of the Diffie-Helman algorithm in communications security?
    • to create password hashes for secure authentication
    • to provide routing protocol authentication between routers
    • to encrypt data for secure e-commerce communications
    • to secure the exchange of keys used to encrypt data
11. Which type of encryption algorithm uses public and private keys to provide authentication, integrity, and confidentiality?
    • symmetric
    • shared secret
    • IPsec
    • asymmetric
12. How do modern cryptographers defend against brute-force attacks?
    • Use statistical analysis to eliminate the most common encryption keys.
    • Use a keyspace large enough that it takes too much money and too much time to conduct a successfulattack.
    • Use an algorithm that requires the attacker to have both ciphertext and plaintext to conduct a successful attack.
    • Use frequency analysis to ensure that the most popular letters used in the language are not used in the cipher message.
13. Which encryption protocol provides network layer confidentiality?
    • IPsec protocol suite
    • Transport Layer Security
    • Secure Hash Algorithm 1
    • Secure Sockets Layer
    • Keyed MD5
    • Message Digest 5
14. Refer to the exhibit. Which encryption algorithm is described in the exhibit?
    
    • RC4
    • AES
    • 3DES
    • DES
    • SEAL
15. Which statement describes asymmetric encryption algorithms?
    • They have key lengths ranging from 80 to 256 bits.
    • They include DES, 3DES, and AES.
    • They are also called shared-secret key algorithms.
    • They are relatively slow because they are based on difficult computational algorithms.
16. Which two non-secret numbers are initially agreed upon when the Diffie-Hellman algorithm is used? (Choose two.)
    • binomial coefficient
    • generator
    • elliptic curve invariant
    • prime modulus
    • topological index
    • pseudorandom nome
17. In what situation would an asymmetric algorithm most likely be used?
    • logging onto a computer
    • making an online purchase
    • uploading a networking book chapter using FTP
    • transferring a large stream of data between two corporate locations
18. Why is asymmetric algorithm key management simpler than symmetric algorithm key management?
    • It uses fewer bits.
    • Only one key is used.
    • Two public keys are used for the key exchange.
    • One of the keys can be made public.
19. What is the purpose of code signing?
    • source identity secrecy
    • integrity of source .EXE files
    • reliable transfer of data
    • data encryption
20. Which algorithm can ensure data confidentiality?
    • MD5
    • PKI
    • RSA
    • AES
21. What is the purpose of a digital certificate?
    • It guarantees that a website has not been hacked.
    • It authenticates a website and establishes a secure connection to exchange confidential data.
    • It provides proof that data has a traditional signature attached.
    • It ensures that the person who is gaining access to a network device is authorized.
22. Fill in the blank.
    A shared secret is a symmetric key used in a encryption algorithm.