Cisco Router – CBAC and Zone Based Firewall Setup
KB ID 0000937 Problem IOS 11.2 gave us CBAC, and IOS 12.4(6)T gave us the Zone Based Firewall. You can still use either, (providing you are running the correct IOS, or in the case of version 15 and upwards, added the correct license, ‘securityK9’). For older IOS versions usually you want the advipservices version of the IOS). Solution Run the following command to see if you have the correct license installed....