By definition, a firewall is a single device used to enforce security policies within a network or between networks by controlling traffic flows.

The Firewall Services Module (FWSM) is a very capable device that can be used to enforce those security policies. The FWSM was developed as a module or blade that resides in either a Catalyst 6500 series chassis or a 7600 series router chassis. The “tight” integration with a chassis offers increased flexibility, especially with network virtualization and the incredible throughput that is not only available today but will increase significantly with the introduction of the 4.x code train.

The look and feel of the FWSM is similar to that of the PIX and ASA. These products are all part of the same family, originating with the PIX and the “finesse” operating system. If you have had any experience with either the PIX or ASA, you will find comfort in not having to learn another user interface.

Having a good understanding of the capabilities offered by the different types of firewalls will help you in placing the appropriate type of firewall to best meet your security needs.