Question:

(a) Describe how IPSec provides data source authentication.

(b) Which protocol can be used to provide limited traffic analysis confidentiality? Why is it "limited"?

(c) What is encapsulation?

(d) Considering the TCP/IP protocol suite, what is the lowest layer at which a firewall can operate?

(e) A company designs and implements software. It needs a web site to sell its products, and needs to be able to forward email from external sources (such as customers) to the developers. But it is concerned about putting systems of the developers' network onto the Internet.

The company hired a consultant, who recommended that the company design a network that included a DMZ.

a. Please explain what a DMZ is.

b. Why did the consultant recommend this?

(f) Explain how a "signature based IDS" works? What is the disadvantage of such an IDS?