Two companies are separately updating their tools for protecting enterprise wireless LANs at this week's Interop trade show in Las Vegas.

Both AirTight Networks and Network Chemistry combine radio frequency sensors and management software to create in effect an alarmed perimeter around a wireless LAN and then take action to block detected threats.

AirTight's new release focuses on dealing with a larger number of threats, tackling several threats at once and automating responses to them. The Network Chemistry release includes a new sensor design that can use Ethernet cable runs and rogue-detection software that can quickly tell you if an authorized device is actually connected to your WLAN.

SpectraGuard Enterprise 3.0 from AirTight, Mountain View, Calif., is designed as a wireless intrusion prevention system. It runs server software on an AirTight Linux-based appliance, collecting radio frequency data from sensors scattered over an office or campus to listen for radio transmissions. The sensors are simply IEEE 802.11b/g and 11a radios configured to only receive signals, and usually tweaked to cover a wider area than a standard WLAN access point.

One key change version 3 is that the software can now detect more than one threat mounted against a specific sensor. In the past, when a sensor detected a rogue transmission, it would zero in on that threat. While the sensor was occupied, that part of the network was unguarded and vulnerable to a second attack. Now, the sensor is able to block the first threat for a longer period of time while quickly shifting between scanning and blocking activities to handle more than one threat.

The new release also can now automatically block or disconnect, not just detect, several key threats: spoofing of access-point MAC addresses, denial-of-service attacks, and the so-called "evil twin," which is a device masquerading as a legitimate WLAN node. All together, SpectraGuard now can detect and take actions against eight different types of RF threats.

Also new is the ability for administrators to move WLAN planning data from a separate PC application, SpectraGuard Planner, directly into SpectraGuard Enterprise. Planner is used to lay out a wireless LAN, juggle the locations of access points and sensors, and create a map showing relative signal strength across the site. By moving this data into SpectraGuard Enterprise, administrators can compare it with actual RF data from the active sensors and create a real-time radio map that shows any holes or gaps in the sensor coverage, and the actual signal strength pattern of the various access points.