This chapter discusses the topic of Network Address Translation (NAT). I first discuss the reasons NAT was created and how NAT is implemented in FireWall-1. Next, I show a step-by-step example of how to implement NAT in a network. I then talk about some of the inherent limitations of NAT and discuss a couple of ways to work around them. Finally, I talk about troubleshooting NAT with a packet sniffer.
By the end of this chapter, you should be able to:
Understand why NAT is necessary
Identify what NAT actually does
Identify why NAT does not always work
Effectively troubleshoot NAT problems with a packet sniffer
Implement a NAT configuration