CSC 360
Fall, 2014
Test 4 Study Guide
CRC








What is the purpose of CRC calculations?
Give a specific example of where the CRC process is used
Give one fact about CRC
How many zeroes are added to the dividend?
What is used as the divisor: the polynomial or the message?
What is used as the dividend: the polynomial or the message?
What is the rule as to how many exclusive-OR gates will be used in the hardware
implemnentation?
Be able to calculate the CRC bits either by long division or by hardware shifting
Chapter 10: Network Security
 Three security goals: confidentiality, integrity, and availability
 Know a specific threat to each of the above
 What is cryptography?
 What is steganography?
 Give an example of each of the above
 What is a symmetric-key cipher?
 What is an asymmetric-key cipher?
 How do these differ? See page 746 for more of a comparison.
 Know the terms: plain text, cipher text, encryption, decryption
 Know the substitution cipher of Figure 10.4
 Know the polyalphabetic cipher of Example 10.4
 How do the two cipers above differ in operation?
 Know the transposition cipher of Figure 10.6
 Alice wants to send an e-mail to Bob using an asymmetric-key cipher. What key does she
need to do this?
 Know general details of RSA cryptosystem – pages 748-751
 What type of algorithm is used to preserve message integrity? Page 751
 Explain the purpose of a digital signature
 What protocols provide security at the Application Layer?
 What protocols provide security at the Transport Layer?
 Why is security needed at the Network Layer (three reasons)? Page 782
 What is the name of the collection of protocols that provide security at the Network
Layer?
 What is a packet-filtering firewall?
 What is a proxy firewall?
 Browse over the Questions and the Problems at the end of Chapter 10 (some of these
were assigned as homework)