The document contains two parts. Part 1 lists review questions about authentication vs authorization, network security relationships, network vs host intrusion detection systems, and VPNs. Part 2 instructs the reader to create a spreadsheet that encrypts values using a transposition cipher, then further encrypts the results using a substitution cipher.

1. Part 1: Review Questions
What is the difference between authentication and
authorization? Can a system permit authorization without
authentication? Why or why not?
What is the typical relationship between the untrusted network,
the firewall, and the trusted network?
How does a network-based IDS differ from a host-based IDS?
What is a VPN? Why are VPNs widely used?
Part 2: Module Practice
Create a spreadsheet that takes eight values into eight different
cells and then applies a transposition cipher to them. Next,
create a row that takes the results and applies a substitution
cipher to them (substitute 0 for 5, 1 for 6, 2 for 7, 3 for 8, 4 for
9, and vice versa).