What is the minimum Cisco IOS version that supports zone based firewalls?
Also question is, what is Zone Based Policy Firewall?
Zone-Based Policy Firewall (also known as Zone-Policy Firewall, or ZFW) changes the firewall configuration from the older interface-based model to a more flexible, more easily understood zone-based model. Interfaces are assigned to zones, and inspection policy is applied to traffic moving between the zones.
- A zone must be configured before an interface is assigned to it and an interface can be assigned to only a single zone.
- All traffic to and from an interface within a zone is permitted.
- All traffic between zones is affected by existing policies.
In this way, what is Cisco zone based firewall?
The Cisco Zone-Based Firewall is the successor of Classic IOS firewall or CBAC (Context-Based Access Control). It primarily deals with the security “zones”. We can assign router interfaces to various security zones and control the traffic between them. The firewall dynamically inspects traffic passing through zones.
Even though ASA devices are considered as the dedicated firewall devices, Cisco integrated the firewall functionality in the router which in fact will make the firewall a cost effective device. The zone based firewall came up with many more features that is not available in CBAC.