Assessment Item 3
Assessment 3
Value: 25%
Due date: 28-Jan-2013
Return date: 18-Feb-2012
Submission method options
EASTS (online)
Task
Task 1. Online Discussions (24 marks)
Below are listed a set of topics. You are required to conduct research and participate
in online/forum discussions on a topic from the set (total of seven topics). In your
discussion postings, you should try and address the following points:
• Provide information about the topic (discuss the topic, describe the relevant
technologies, applications of the technologies, clarify vague areas of other
students postings, etc.)
• Raise questions about the information provided by other students (this must be
done in an adequately professional manner)
• Respond to questions raised about your own information and other student's
• Contribute to discussions in general
Note that the aim of this task is:
• To build an understanding and perspective of current hot topics in Network
Security; and
• To build generic skills including, but not limited to
o A capacity for teamwork and collaboration
o An ability for critical thinking, analysis and problem solving
o Gaining or improving information technological literacy
o A capacity for lifelong learning and an appreciation of its necessity
As such, the more you contribute the development of these topics and related
discussion the more likely you will score well in this task.
Topics Set
1. The security risks associated with using passwords for internet authentication
2. The privacy implications of data collected by Google, Facebook and other
(social) networking sites
3. Encrypting more and more internet services with SSL (HTTPS) by default
4. The security risks around BYOD (Bring Your Own Device) in the workplace
5. The security risks around using Cloud Computing
6. The security risks to critical infrastructure (such as power, communication,
water) from malicious cyber attacks
7. Offering financial rewards for finding security vulnerabilities in software
Your submission
You are required to prepare and submit a report on your topic to address the following
questions:
1. Summarise the topic and the issues discussed. Discuss how your own posts
contributed to this knowledge.
2. Based on your own research, discuss whether or not the summary presented in
(1) is accurate.
3. Identify any important issue/s that you believe were not addressed, or not
addressed adequately in the discussions. Explain why you view this
issue/these issues as important.
4. Discuss what you believe to be the most important lesson you have learnt as
a result of these discussions. Explain the impact of this and its
application/impact in real life.
Task 2: Understanding RSA (12 marks)
The general method for constructing the parameters of the RSA cryptosystem can be
described as follows
• Select two primes ?? and ??
• Let ?? = ???? and determine Ø ?? = (?? - 1)(?? - 1)
• Randomly choose ?? in the range 1
• Determine ?? as the solution to ???? = 1 mod Ø ??
• Publish (??,??) as the public key
a) Show that a valid public key pair can still be constructed if we use only one prime
??, such that ?? = ?? and Ø ?? = (?? - 1).
b) If we use this “one-prime” RSA construction and publish the public key ??,?? ,
why is it easy to recover the secret key ???
c) Let ??????(??) denote the encryption of the message ?? using the pair ??,?? . Show
that the RSA encryption function has the following property for any two messages
??1 and ??2
?????? ??1 × ??2 = ?????? ??1 × ?????? ??2
That is, the encryption of a product is equal to the product of the encryptions.
Task 3: Security infrastructure and protocols (15 marks)
a) PKI and PGP are two methods for generating and managing public keys for use
in protocols such as secure email. Compare and contrast the trust models for
public keys used in PKI and PGP, and assess the statement that a PKI is a “topdown”
approach to trust and PGP is a “bottom-up” approach to trust.
b) The SSL protocol uses (X.509) certificates to create a secure session between a
server and a client in a web session. Discuss the browser-based trust model
assumed in SSL, and compare it with the trust model used in Kerberos.
Kerberos is designed to operate is a relatively small domain, such as a single
company. Discuss the practical issues around extending the Kerberos trust
model to a global scale, say to provide secure services between Amazon and its
customer base.
c) Both IPsec and SSL provide encrypted network communication, but at different
layers in the Internet protocol stack, and for different purposes. Compare and
contrast these two protocols, and describe the secure communication scenarios
they are best suited to address.
Rationale
This assessment item relates to the learning outcomes (subject objectives) and
provides an opportunity for you to
• Demonstrate factual knowledge, understanding and application of state-ofart
network security;
• Demonstrate ability to integrate and apply information from various topics and
to apply understanding and knowledge to a practical situation;
• Demonstrate ability to work in a team, sharing knowledge; and
• Demonstrate an understanding of the RSA cryptosystem
• Being able to provide coherent descriptions of network security protocols and
services, and be able to recognize the need for distinct protocols at different
layers in Internet security.
Marking Criteria
Task 1: Marking Scale
• Correct and concise summary of the issues discussed in forum (6 Marks)
• Analysis of the summary (4 Marks)
• Discussion of the important/missing issues not addressed in the forum (6 Marks)
• Discussion of the learning and exploring the impacts in real life (8 Marks)
Task 2: Marking Scale
a) Show that “one-prime” construction produces a valid public key (4 Marks)
b) Show the steps to recover ?? (4 Marks)
c) Mathematical argument to show the property (4 Marks)
Task 3: Marking Scale
a) Compare and contrast the trust models (5 Marks)
b) Compare and contrast the trust models (3 Marks), implementing Kerberos on a
large scale (2 marks)
c) Compare and contrast the protocols (3 Marks), best suited scenarios (2 Marks)
Requirements
• Your submission must be in a form readable by Microsoft Word format.
• Each question should be answered individually with the corresponding label to
indicate the tasks completed e.g. Task 1 a.
• Your submission must be not more than 10 pages long (including diagrams), must
have margins no less than 2cm, and font size no less than 12 point. Oversized
assignments will be penalised.
• A cover page (outside the page limit) must be included and should contain
relevant identifying information.
• Appropriate referencing (APA 6th edition) must be used throughout the document
with the bibliography not counted in the page limit.
• Your discussion postings are considered part of your assignment submission and
are thus subject to Faculty regulations for academic misconduct (including
plagiarism). As such, any text adapted from any source must be clearly labelled
and referenced. You should clearly indicate the start and end of any such text.
• Your discussion postings will be used required to complete your assignment but
do not directly form part of the assessment of the assignment. As such, no formal
feedback will be provided regarding your discussions.