Considerations for Sensor Placement with WEP Cloaking

For effective WEP Cloaking, there are two important considerations:

• Spatial coverage - The sensors enabled with WEP Cloaking must at a minimum cover the same area as the s and wireless clients they are protecting.

  For this requirement, you should leverage any site surveys you conduct or have conducted for placement of s as aids to sensor placement decisions. Another option is using a WLAN simulation tools such as LAN Planner.

  For example, in a typical retail location most wireless point-of-sale devices will be in the front of the store near the check-out stations. Assuming the hacker would be outside of the building, sitting in the front parking lot, it would make sense to place at least 2 sensors in each of the corners in the front of the store. If there is public access from the back of the building or the retail location is surrounded by parking areas, you may want to consider additional sensors in the back for complete protection.

• Channel coverage - A single sensor should not be required to cloak more than 3 s at a time.

  For effective cloaking there must be sufficient chaff WEP frames to confuse the statistical WEP cracking tools. At the same time, the sensors must perform regular Wireless IPS scanning on other channels. The sensors are designed to intelligently adjust their frequency scanning patterns. However, to maximize cloaking effectiveness and scan all other channels for possible intrusions, sensors should not be expected to cloak more than three APs, or more specifically three unique communication channels at a time.