firewalling...

cbac

http://www.cisco.com/en/US/products/sw/secursw/ps1018/products_tech_note09186a0080094e8b.shtml


The Context-Based Access Control (CBAC) feature of the Cisco IOS® Firewall Feature Set actively inspects the activity behind a firewall. CBAC specifies what traffic needs to be let in and what traffic needs to be let out by using access lists (in the same way that Cisco IOS uses access lists). However, CBAC access lists include ip inspect statements that allow the inspection of the protocol to make sure that it is not tampered with before the protocol goes to the systems behind the firewall.

zbfw

http://www.cisco.com/en/US/products/sw/secursw/ps1018/products_tech_note09186a00808bc994.shtml#topic1


Cisco IOS Classic Firewall stateful inspection (formerly known as Context-Based Access Control, or CBAC) employed an interface-based configuration model, in which a stateful inspection policy was applied to an interface. All traffic passing through that interface received the same inspection policy. This configuration model limited the granularity of the firewall policies and caused confusion of the proper application of firewall policies, particularly in scenarios when firewall policies must be applied between multiple interfaces.

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. Inter-zone policies offer considerable flexibility and granularity, so different inspection policies can be applied to multiple host groups connected to the same router interface.