Protecting wireless local area networks from intrusion by eavesdropping on the eavesdroppers and dynamically reconfiguring encryption upon detection of intrusion

摘要

The present invention involves the recognition that since an eavesdropper listening adjacent to a wireless LAN is likely to be mobile and operating on a short time cycle, he himself is likely to be wirelessly transmitting his test message. Consequently, the present invention provides the combination of apparatus for eavesdropping within an area layer adjacent to and surrounding the LAN area periphery for potential wireless transmissions of an intruder having a lower frequency within a level below the LAN frequency and addressed to the network location of any one of the computer terminals in the LAN; and an implementation responsive to said eavesdropping means for changing the encryption code of said encrypted wireless transmission upon the eavesdropping detection of a wireless transmission of said lower frequency addressed to a network location of one of the terminals in said LAN. There is the recognition that there are several factors contributing to the success of the process of the invention. It is likely that the intruder must send his message at a lower frequency than the 2.4 GHz frequency of the LAN area transmissions because the intruder will probably have to reach a base station tower over a longer distance or range than the adjacent target wireless LAN facility. This insures that the eavesdropping of the present invention will be at a lower frequency and, thus, not interfered with by the transmissions within the LAN.