Properly configured access points and clients are useless without a secure connection to other networks. Whether your gateway connects you to your intranet or proves transit to the greater Internet, it is the keystone of your security architecture. It is a central point for traffic to transfer through on its way to other networks. It is an excellent place to enforce a single security policy. Unfortunately, many networks do not make proper use of this keystone. Either through misconfiguration, or a complete lack of firewalling capability, networks around the world are wide open to attack. When the gateway is connected to a wireless network, the risk increases. Attackers are now on the doorstep of your valuable resources, and the role of the gateway becomes more important. The next four chapters will show you how to architect and configure a gateway that protects your wired and wireless resources.