The heart and soul of every firewall are the security zones. In this section, we will discuss how Palo Alto Networks firewalls segment traffic into zones. This is how traffic and interfaces are assigned to classified identities in the firewall, by selecting the right interface type and providing its respective address on the network. We will take advantage of having V-Wires, removing physical layer 1 constraints and points of failure, while providing a simplified network security topology. Understanding this section is a key topic in Mastering Palo Alto Networks.