Task 1. Online Discussions

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.
  
Task 2: Security infrastructure and protocols
 
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 "top-down" 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.