CMGT 431 WEEK 2 LEARNING ASSIGNMENT CHAPTER 5

CMGT 431 WEEK 2 LEARNING ASSIGNMENT CHAPTER 5

1 A secret message has been encrypted with a key that is as long as the message itself. The key will be used for only this message. The type of encryption used here is:
a. Running key cipher
b. One-time cipher
c. One-time pad
d. Diffie-Hellman


2. The weakness of a monoalphabetic cipher is:
a. It is vulnerable to frequency analysis
b. It requires excessive computing resources
c. The key is embedded in the ciphertext
d. The key is too short



3. DES, AES, and CAST are examples of:
a. SSL encryption algorithms
b. Public key cryptography algorithms
c. Stream cipher algorithms
d. Block cipher algorithms



4. Advanced Encryption Standard uses the:
a. Twofish cipher
b. Reykjavík cipher
c. Rijndael cipher
d. Keccak cipher



5. The disadvantage of electronic codebook is:
a. It is a manual encryption algorithm not suited for use in computers
b. It is a patented encryption algorithm
c. Each identical plaintext block encrypts into an identical ciphertext block
d. It uses a 56-bit encryption key that is considered too short



6. RC4 is an example of a:
a. Message digest
b. Stream cipher
c. Block cipher
d. Key exchange



7. SHA-1 is an example of a:
a. Message digest
b. Stream cipher
c. Block cipher
d. Key exchange



8. Public key cryptography is so-named because:
a. It is highly popular
b. Its use is not restricted by patents
c. It utilizes an open source encryption algorithm
d. The key that is used to encrypt a message does not need to be kept a secret but 



9. Two parties wish to exchange encrypted messages using symmetric key cryptography.
The parties do not have an out-of-band method for exchanging keys. The parties should use:
a. A stream cipher
b. Message digests
c. Public key cryptography
d. Diffie-Hellman key exchange



10. Frequency analysis refers to:
a. Analyzing the rate of occurrence of characters in ciphertext
b. Eavesdropping on spread-spectrum radio frequency transmission in order to harvest encryption keys
c. Analyzing the rate of occurrence of characters in plaintext
d. Analysis of emanations in order to harvest encryption keys



11. An attacker is trying to crack an encryption scheme in order to discover secret information.  The attacker is able to get his own plaintext messages encrypted by the same mechanism used to protect the secret information he is trying to obtain. This method of attack is known as:
a. Chosen plaintext attack
b. Chosen ciphertext attack
c. Cryptanalysis
d. Man in the middle



12. An attacker is trying to discover the contents of encrypted messages that he can easily intercept. The attacker attempts to break messages by intercepting and substituting his own messages in a communications stream between two parties. This type of attack is known as:
a. Unknown plaintext
b. Known ciphertext
c. Man in the middle
d. Replay



13. An administrator wants to have all traffic between two servers encrypted. The administrator should use:
a. PGP
b. IPsec in transport mode
c. IPsec in tunnel mode
d. SSL



14. Cookies are suited for session management:
a. When the session or user ID is encrypted
b. If the session is encrypted with SSL/TLS
c. Only as a last resort
d. Only on a protected LAN or VPN



15. VPNs can be used to protect network traffic:
a. Between any nodes on two different networks
b. Between a station and any node on a network
c. Between two stations
d. All of the above