Cryptography | Information Technology

Assignment

Task 1

What does CIA stand for in the context of computer security?

Task 2

List 5 general design decisions that have to be made while constructing secure systems.

Task 3

Given that the substitution-box(ie S-box) is shown as below

    |  00   01   10   11

 —|——————————-

 00 | 0011 0100 1111 0001

 01 | 1010 0110 0101 1011

 10 | 1110 1101 0100 0010

 11 | 0111 0000 1001 1100

what are the substitutions for the decimal numbers 12, 7, and 2

                                                                                          

Task 4

Read the paper of FIPS 197, which describes an implementation of the AES. Understand the Key Expansion algorithm shown in Figure 11.

When a cipher key is

2b7e151628aed2a6abf7158809cf4f3c

for Nk=4, which results in

w[0]=2b7e1516, w[1]=28aed2a6, w[2]=abf71588,w[3]=09cf4f3c

what will be w[4], w[5], w[6], w[7]?

Task 5

Choose a topic from the following list to be the research topic of your assignment 3. Assignment 3 is a reading research project, that require a lot of reading and analysis. A report probably less than 1 page shall be given in the submission:

1. Critically Reviewing DES and AES
2. Understanding the Kerberos Systems and Kerberos Authentication Protocols
3. Using OpenSSL to generate Digital Certificates
4. What are and How to do with the security and authentication of Websites?