1. BAIT1103 INTERNET SECURITY
Tutorial 2
1. What is message authentication?
2. What is a message authentication code?
3. What is a one-way hash function? How is it different from message authentication
code?
4. List the design objectives for HMAC.
5. Explain what you understand with digital signature.
Past Years Questions:
1. (i) What is the purpose of hash functions?
(ii) Explain how hash functions are used in storing password file and integrity
check of downloaded files by providing each step in detail.
2. State ONE (1) purpose of secure hash functions and provide TWO (2) examples
of how the secure hash functions are being applied.
3. With the aid of a diagram, illustrate how the Hash Message Authentication Code
(HMAC) algorithm structure derives from the Hash functions and Message
Authentication Code (MAC).
4. Do you agree that message authentication without encryption is better than
message authentication with encryption? Justify your answer.
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2. BAIT1103 INTERNET SECURITY
5. Figure 1 below shows the process of a message transmitting from a sender to a
receiver by using the security of Message Authentication.
i.
Name the component A, B, K as stated in Figure 1.
ii.
Component C is a process. Name the process and briefly explain the
purpose of this component in Figure 1.
iii.
With the aid of Figure 1, briefly describe the steps of the Message
Authentication process from the sender to the receiver.
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