Configuring Cisco ZFW - Cisco Zone Based Firewall

The concept of Cisco Zone Based Firewall (ZFW) is very simple yet can quickly turn into a giant two headed dog if you don't understand how to design it. ZFW basically classifies interfaces into security zones and Intra-zone interfaces can pass traffic freely between each other however traffic between Inter-zone interfaces is restricted by default. A quick example can shed more light on this concept.

Consider the simple topology below and let's get started.
  

Configuring CBAC - Context Based Access Control

When it comes to security, I think you should always implement an actual firewall such as an ASA. However if you are a small business and you needed to get a stateful firewall up and running then Cisco Context Based Access Control is the way to go. It's lightweight, easy to configure and it gets the job done.

Consider this topology below and let's see how easily we can get it configured.