Thus, you shouldn't implement MAC filtering thinking it will do much for security, but maybe as a way to loosely control which computers and devices end-users bring onto the network. But also consider the management nightmare you might face to keep the MAC list up-to-date.
9. Do limit SSIDs users can connect to
Many network administrators overlook one simple but potentially dangerous security risk: users knowingly or unknowingly connecting to a neighboring or unauthorized wireless network, opening up their computer to possible intrusion. However, filtering the SSIDs is one way to help prevent this. In Windows Vista and later, for example, you can use the netsh wlan commands to add filters to those SSIDs users can see and connect to. For desktops, you could deny all SSIDs except those of your wireless network. For laptops, you could just deny the SSIDs of neighboring networks, enabling them to still connect to hotspots and their home network.
10. Do physically secure network components
Remember, computer security isn't just about the latest technology and encryption. Physically securing your network components can be just as important. Make sure access points are placed out of reach, such as above a false ceiling or even consider mounting access points in a secure location and then run an antenna to an optimum spot. If not secured, someone could easily come by and reset an access point to factory defaults to open access.
11. Don't forget about protecting mobile clients
Your Wi-Fi security concerns shouldn't stop at your network. Users with smartphones, laptops, and tablets may be protected onsite, but what about when they connect to Wi-Fi hotspots or to their wireless router at home? You should try to ensure their other Wi-Fi connections are secure as well, to prevent intrusions and eavesdropping.
Unfortunately, it isn't easy to ensure outside Wi-Fi connections are secure. It takes a combination of providing and recommending solutions and educating users on the Wi-Fi security risks and prevention measures.
First, all laptops and netbooks should have a personal firewall (such as Windows Firewall) active to prevent intrusions. You can enforce this via Group Policy if running a Windows Server or use a solution such as Windows Intune to manage non-domain computers.
Next, you need to make sure the user's Internet traffic is encrypted from local eavesdroppers while on other networks by providing VPN access to your network. If you don't want to use in-house VPN for this, consider outsourced services such as Hotspot Shield or Witopia. For iOS (iPhone, iPad, and iPod Touch) and Android devices, you can use their native VPN client. However, for BlackBerry and Windows Phone 7 devices, you must have a messaging server setup and configured with the device in order to use their VPN client.
You should also make sure any of your Internet-exposed services are secured, just in case the user doesn't use the VPN while on a public or untrusted networks. For instance, If you offer email access (client or Web-based) outside of your LAN, WAN or VPN, ensure you use SSL encryption to prevent any local eavesdroppers at the untrusted network from capturing the user's login credentials or messages.
Geier is a freelance tech writer -- become a Twitter follower to keep up with his writings. He's also the founder of NoWiresSecurity, which helps businesses easily protect their Wi-Fi network with Enterprise (802.1X) security.
Read more about wide area network in Network World's Wide Area Network section.