Even if you do not have a wireless network (WLAN), you need to watch out for Rogue APs on your LAN.

If you are responsible for provisioning, operating or managing a Wireless LAN (a WLAN), it is imperative that you proactively be on a look out for Rogue APs and unauthorized Wireless Routers/Bridges or Repeaters that someone may have sneaked within (or in close proximity of) your wireless network.

Considering that a large majority of Rogue APs are found to be consumer-grade (cheap) unmanaged devices, they are particularly difficult to discover -especially if your own network is built using similar (cheap, unmanaged) networking devices. If your network has been properly designed (to be security-centric), and has been implemented using enterprise grade (managed) networking hardware, detecting uninvited/rogue devices within your networking space is not very difficult.

One of the ill-effects of changing the default SSID on your Access Points/Routers, and disabling SSID broadcast on your Access Points/Routers, is that your access point becomes invisible to everyone -including your own wireless client PCs, PDAs, and all your other wireless networking devices.

Therefore, unless you configure your wifi clients to connect (only) to that particular trusted AP or Wireless Router of yours that is no longer announcing itself to the world, wireless adapter cards installed in your wireless-enabled computers are not going to find your APs, WiFi Routers or Wireless Gateways. As soon as you power up your wireless clients, they will most likely default to looking/scanning around for any available APs. It is very possible, therefore, that if any of your (friendly?) neighbor happens to be running an AP (or a wireless gateway) that broadcasts a factory default SSID, your wireless adapter cards are going to discover it, and will try and get associated with it. It should be no surprise that most wireless intruders like to just show up in their victim’s wifi-space with an AP that is setup to broadcast one of those factory default SSIDs; and configured to happily allow anyone that is ignorant enough to want to get connected with their rogue AP.