Location-based access control for wireless local area networks
A wireless local area network (LAN), and a method of operating the same, prevents unauthorized users from accessing the wireless LAN. A signal strength of a station attempting to access the wireless LAN is measured. If the signal strength is less than a predetermined threshold value, the system concludes that the station is outside of an authorized geographical area. Such a station attempting to establish a connection is characterized as an unauthorized station, and access to the wireless LAN is denied. The system may also periodically verify that authorized stations remain within the authorized geographical area. A station that has moved outside of the authorized geographical area can be notified or denied further access to the wireless LAN.
1. A method of operating a wireless local area network comprising the steps of:
receiving a request from a wireless station at an access point of the wireless local area network;
determining if a location of the wireless station is within a predefined geographical area;
if the location is within the predefined geographical area, allowing the wireless station to access the wireless local area network; and
if the location is outside the predefined geographical area, denying the wireless station access to the wireless local area network, wherein said step of determining includes the steps of:
measuring a signal strength of the wireless station as received by the access point of the wireless local area network; and
comparing the signal strength to a predetermined threshold value, wherein the predetermined threshold value is set such that reliable signals could be received at the access point from the wireless station with a signal strength less than the predetermined threshold value, however signal strengths less than the predetermined threshold value received at the access point are assumed to come from an unauthorized wireless station outside the predefined geographical area and are denied access to the wireless local area network.
2. The method according to claim 1 , further comprising the steps of:
checking a key code transmitted by the wireless station after said step of allowing the wireless station to access the local area network;
if the key code matches a preset key code, allowing the wireless station to utilize one or more services provided on the wireless local area network; and
if the key code fails to match a preset key code, denying the wireless station access to utilize services provided on the wireless local area network.
3. The method according to claim 1 , further comprising the step of:
periodically verifying that all wireless stations accessing the wireless local area network remain within the predefined geographical area.
4. The method according to claim 3 , wherein if a wireless station moves outside of the predefined geographical area, activating a control policy regarding permitting continued access to the wireless local area network for the wireless station outside the predefined geographical area.
5. The method according to claim 4 , wherein the control policy includes denying the wireless station outside the predefined geographical area access to the wireless local area network.
6. The method according to claim 5 , wherein the control policy also includes resetting state variables stored in a memory of the wireless station outside the predefined geographical area.
7. The method according to claim 4 , wherein the control policy includes determining if a data transfer is in progress between the wireless local area network and the wireless station, and if so, continuing the data transfer until completion, and then denying the wireless station outside the predefined geographical area access to the wireless local area network.
8. A system comprising:
an access point for receiving a wireless request from a wireless station;
a control unit for determining if a location of the wireless station is within a predefined geographical area; and
a router or bridge for providing the wireless station access to a wireless local area network, if the wireless station is within the predefined geographical area, wherein said control unit includes:
a signal strength measuring device for measuring a signal strength of a signal received by said access point from the wireless station, and wherein said system further comprises:
a memory storing a predetermined threshold value, and wherein said control unit includes a comparator for comparing a measured signal strength received by said access point from the wireless station to said predetermined threshold value, wherein said predetermined threshold value is set such that reliable signals could be received at said access point from the wireless station with a signal strength less than said predetermined threshold value, however signal strengths less than said predetermined threshold value received at said access point are assumed to come from an unauthorized wireless station outside the predefined geographical area and are denied access to the wireless local area network.
9. The system according to claim 8 , wherein said control unit also includes:
a timer, wherein said control unit monitors said timer, and after a predetermined time, said control unit determines if a location of the wireless station remains within the predefined geographical area.
10. A system comprising:
a wireless station;
an access point receiving a wireless request from said wireless station;
a control unit determining if a location of said wireless station is within a predefined geographical area; and
a router or bridge for providing said wireless station access to a wireless local area network, if said wireless station is within the predefined geographical area, wherein said control unit includes:
a signal strength measuring device for measuring a signal strength of a signal received by said access point from said wireless station, and wherein said system further comprises:
a memory storing a predetermined threshold value, and wherein said control unit includes a comparator for comparing a measured signal strength received by said access point from the wireless station to said predetermined threshold value, wherein said predetermined threshold value is set such that reliable signals could be received at said access point from said wireless station with a signal strength less than said predetermined threshold value, however signal strengths less than said predetermined threshold value received at said access point are assumed to come from an unauthorized wireless station outside the predefined geographical area and are denied access to the wireless local area network.
11. The system according to claim 10 , wherein said control unit also includes:
a timer, wherein said control unit monitors said timer, and after a predetermined time, said control unit determines if a location of said wireless station remains within the predefined geographical area.
12. A method of setting up a wireless local area network comprising the steps of:
providing an access point for transceiving communications with wireless stations inside a predefined geographical area;
operating a wireless station within the predefined geographical area, which is smaller than an area which could be reliably served by the access point;
measuring signal strengths received at the access point from the wireless station, as the wireless station is moved about within the predefined geographical area;
setting a predetermined threshold value at an amount less than the lowest measured signal strength; and
storing the predetermined threshold value in a memory, wherein the predetermined threshold value is set such that reliable signals could be received at the access point from the wireless station with a signal strength less than the predetermined threshold value, however signal strengths less than the predetermined threshold value received at the access point are assumed to come from an unauthorized wireless station outside the predefined geographical area and are denied access to the wireless local area network.
13. The method according to claim 12 , further comprising the steps of:
uniquely identifying a first wireless station to communicate with the access point; and
storing a first control policy in the memory to deal with the first wireless station, wherein the first control policy includes parameters for handling communications between the access point and the first wireless station when the first wireless station moves outside of the predefined geographical area.
14. The method according to claim 13 , further comprising the steps of:
uniquely identifying a second wireless station to communicate with the access point; and
storing a second control policy in the memory to deal with the second wireless station, wherein the second control policy includes parameters for handling communication between the access point and the second wireless station when the second wireless station moves outside of the predefined geographical area, wherein the second control policy is different from the first control policy.