A security zone is a grouping of interfaces. Zones divide the network into segments to help you manage and classify traffic. You can define multiple zones, but a given interface can be in one zone only.
The Firepower system creates the following zones during initial configuration and they are displayed in Defense Orchestrator's object page. You can edit zones to add or remove interfaces, or you can delete the zones if you no longer use them.
- inside_zone—Includes the inside interface. This zone is intended to represent internal networks.
- outside_zone—Includes the outside interface. This zone is intended to represent networks external to your control, such as the internet.
Typically, you would group interfaces by the role they play in your network. For example, you would place the interface that connects to the internet in the outside_zone security zone, and all of the interfaces for your internal networks in the inside_zone security zone. Then, you could apply access control rules to traffic coming from the outside zone and going to the inside zone.
Before creating zones, consider the access rules and other policies you want to apply to your networks. For example, you do not need to put all internal interfaces into the same zone. If you have 4 internal networks, and you want to treat one differently than the other three, you can create two zones rather than one. If you have an interface that should allow outside access to a public web server, you might want to use a separate zone for the interface.