Establishing a wireless firewall

After you have carefully examined your WLAN and have taken every precaution possible to control the access mechanisms to any potentially vulnerable parts of your network,
you can install a carefully configured firewall that is deployed between
the wired Ethernetwork within your organization and your wireless network
near your access point. This type of protection is an essential element
that most companies neglect to install.

The WLAN is the most vulnerable part of your network because anyone
can access resources without being physically within your corporate
office buildings. If you install a firewall, then you can effectively block
off access from any incoming wireless client into the protected resources
of your wired network. This level of protection is essential and allows
you to make certain that if your WLAN access controls do fail, you have
the firewall preventing any malicious or unauthorized users from gaining
access to resources that should most definitely stay off limits to all
unauthorized users.