Monitoring a Wireless Network
There are 4 primary methods of monitoring a Wired or Wireless network.
Log Checking The most basic way to monitor your Wireless Network or LAN is by simply checking the Wireless Router logs or by checking the logs of central switches in a large organization. This can show you who is currently on a network and can not be hidden by firewalls.
Monitoring Software The next easiest way to monitor your network is by using hardware level Network Monitoring Software. Programs such as Hardping provide basically the same information as a Wireless Router log file, or a central switch Mac Address listing. They are usually easier to use then searching through different log files, but provide only the basic information of who is currently on the network or who has been on the network since the Router was last rebooted or restarted.
Wireless Intrusion Detection Software This can also be called Hardware Intrusion Detection Software. Essentially, what happens is that software like Who Is On My Wifi takes the same information that is provided by Network Monitoring Software or Wireless Router logs, and compares the information that it receives against a known white list for the network.
Wireless Intrusion Prevention Software It works exactly the same as the Wireless Intrusion Detection Software in identifying an Intruder, but it goes one step further in actually eliminating the Intruders ability to stay joined through the network. There are several methods for forcing the Unknown computer to either disconnect from the network, or what is more common is for the unknown computer to simply be denied any kind of network resources.