Twenty years ago, employees started sneaking PCs into the office, under the radar of mainframe-oriented IT departments. Now, tens of thousands of unauthorized wireless LAN hardware devices called access points (AP) have popped up in enterprise networks, according to analysts, vendors and users. The majority of these rogue APs are being brought in through the back door without the IT unit’s knowledge. They’re installed by employees who crave mobility and don’t mind spending US$200 or less for a wireless AP.