One of the major components of securing a system or network is keeping the “bad guys” out while letting the “good guys” have the access they need. This means you need to make sure that network access to your systems is secure and stable.
Creating firewalls gives you the ability to allow or block network connections. A firewall can inspect each network packet and determine if the packet should be allowed in. In this chapter, you learn the essentials to creating firewalls.
After reading this chapter and completing the exercises, you will be able to do the following:
Identify the essential components of a firewall.
Create a firewall to control access to a system or network.
Block access to external systems.
Configure NAT (Network ...