If you are using wireless connectivity in your network, you have added another way to access your LAN that doesn’t require getting past your firewall, and doesn’t even require physical access!

By default, most wireless access points and devices are set up to connect as transparently as possible, with automatic detection of the wireless node, automatic handshaking and assignment of an IP address, and so on.  This makes it easy for you and your co-workers to connect, but it also means that anyone in the next office, in the  parking lot, on the sidewalk, in a nearby building – anywhere within the bubble of connectivity – may also be able to tap into your bandwidth and go online through your access point without your knowledge or permission.  Worse, they may be able to access not only the internet, but your PCs and servers too!

So, what can you do?  Here are a few basic steps you can do to protect your network.

1.  Turn off SSID Broadcasts.  SSID is the Service Set Identifier, it’s the name of your wireless network.  If broadcast is enabled, your network is continuously “shouting” this ID across the airwaves, where anyone can pick it up.

2.  Change your SSID name.  Too many sites leave this name at the default.  For example, the default SSID for Linksys Access Points is “Linksys”.  Hackers know this, change it to something they don’t know or can guess.  Also, be sure to change the password for maintenance and changes to the wireless access point.  The defaults are also widely known.

3. Implement the strongest form of wireless encryption available for your Wireless Application Protocol (WAP). If your WAP does not support Wi-Fi Protected Access (WPA) or WPA2, it is still better to enable the Wired Equivalent Privacy (WEP) security protocol than to have no encryption at all. But if you do implement WEP, be sure to regularly modify the WEP key to protect against attacks against the WEP key.

4.  Filter access by MAC address.  The MAC address is a unique number associated with each network card.  By entering all the MAC addresses of the computers in your network into the appropriate area of your wireless access point, you can limit access to only known and approved devices.

None of these measures are foolproof, but by adopting them, you can gain a much greater level of security for your wireless network.  New products are on the way that will address this issue, but the above steps are things you can do right now.

More Info: 

Locking The Wireless Network

10 Top Tips For Protecting Yourself At Hotspots