Multiple Choice Questions:
1. Which property must a cryptographic hash function satisfy to ensure it is computationally
infeasible to find two different data objects with the same hash result?
a) One-way property b) Collision-free property c) Confidentiality d) Symmetric encryption
2. What type of attack seeks to find two messages that produce the same hash value using the
"birthday paradox"?
a) Brute-force attack b) Cryptanalysis attack c) Pre image attack d) Birthday attack
3. Which of the following is an example of "something the individual knows" in the context of user
authentication
a) Fingerprint b) Personal Identification Number (PIN) c) Cryptographic keys d) Smart cards
4. Which of the following protocols is most commonly used for one-way authentication?
a) Needham-Schroeder Protocol b) Kerberos c) PKI d) A simple password verification mechanism
5. Which of the following is a security service provided by Pretty Good Privacy (PGP)?
a) Compression b) Authentication c) Data Backup d) Data Recovery
6. In PGP, what is used to generate the hash code for a message?
a) RSA b) SHA-1 c) DES d) AES
7. What encryption algorithm is used in PGP to encrypt the session key?
a) RSA b) AES c) IDEA d) CAST-128
8. Which encryption algorithm is considered strong for securing web communications in modern
protocols?
a) RSA b) AES c) DES d) RC4
9. Which type of firewall is also known as a proxy server?
a) Packet-filtering router b) Stateful firewall c) Application-level gateway d) Circuit-level gateway
10. Which type of firewall does not examine the contents of traffic but simply ensures that a
connection is valid before forwarding traffic?
a) Application-level gateway b) Stateful firewall c) Circuit-level gateway d) Packet-filtering router
Fill in the Blanks:
1. A ________ hash function protects against an attack in which one party generates a message for
another party to sign. [STRONG]
2. The ________ of a message is encrypted with a user's private key to create a digital signature.
[hash value]
3. In a Kerberos environment, a Kerberos server must have the __________ and hashed passwords
of all participating users in its database [USER ID]
4. In a symmetric encryption-based authentication protocol, "something the individual possesses"
could include __________ [cryptographic keys, smart cards, or electronic keycards]
5. A firewall that operates at the transport and network layer and filters traffic based on IP addresses
and port numbers is called a _____________. [Packet-filtering router]
True or False:
1. The use of a hash function in message authentication ensures that the identity of the sender is
always confidential. [F]
2. SHA-1 produces 160-bit hash values and is based on the design of the MD4 hash function. [T]
3. Mutual authentication ensures that both parties in a communication process are verified by each
other [T]
4. In a one-way authentication protocol, the recipient only verifies the identity of the sender, and
not vice versa [T]
5. Firewalls can prevent attacks that bypass them, such as social engineering or insider threats. [F]
