Proactive load distribution for 802.111-based wireless LANs
View Patent ↗A wireless communication system is able to balance load in a wireless network based on radio frequency (RF) utilization, signal strength, quality of signal (QoS), and other measures. The load may be dynamically moved to other wireless access points within the wireless network based on the amount of load on one or more of the access points and on the measures. As such, at different load conditions, the system can change the methods of how to determine which access point should handle a communication session. Further, the system provides methods for proactively adjusting the load in the wireless network before any one access point reaches its capacity.
1. A method for measuring factors related to load balancing in a wireless network, the method comprising:
a processor determining at least an over-the-air utilization at one or more access points;
from the determined at least the over-the-air utilization, the processor determining if there is an access load at the one or more access points, wherein determining the at least an over-the-air utilization comprises determining a radio frequency (RF) utilization for each of one or more radios associated with the one or more access points and wherein determining the RF utilization comprises:
based on a frame size of one of more frames communicated between the one or more access points and at least one mobile device, and a data rate (PHY) for the one or more frames, the processor determining a transmission time for the one or more frames;
the processor adding overhead time to the determined transmission time;
the processor summing the added overhead and determined transmission times for at least two communication sessions associated with a data air time;
the processor dividing the data air time by a measurement time to determine the RF utilization;
the processor measuring a signal strength between the one or more access points and the at least one mobile device;
the processor measuring a quality of a signal for a communication with the at least one mobile device; and
the processor moving an access load to one or more other access points with lower over-the-air utilization.
2. The method as defined in claim 1 , wherein the determined RF utilization, the measured signal strength, and the measured quality of the signal are provided to a control server and wherein the access load is a function of one or more of the determined RF utilization, the measured signal strength, and the measured quality of the signal.
3. The method as defined in claim 1 , wherein an access load on the one or more access points is determined from at least one of the group comprising: the RF utilization, the signal strength, and the quality of the signal measurements.
4. The method as defined in claim 1 , wherein a control server:
receives the RF utilization, the signal strength, and the quality of the signal measurements from two or more access points;
determines an access load on each of the two or more access points based on the RF utilization, the signal strength, and the quality of the signal measurements; and
shifts an access load from a first access point to a second access point based on the determined access loads of the first access point and the second access point.
5. The method as defined in claim 4 , wherein the access load from the first access point is shifted proactively.
6. The method as defined in claim 4 , wherein the access load from the first access point is shifted based on a request for a new communication session.
7. The method as defined in claim 4 , wherein the access load from the first access point is shifted from the first access point with a higher RF utilization and a higher signal strength to the second access point with a lower RF utilization and a lower signal strength.
8. The method as defined in claim 4 , wherein the access load from the first access point is shifted from the first access point with lower RF utilization and a lower signal strength to the second access point with a higher RF utilization and a higher signal strength.
9. A non-transitory computer readable medium, stored on a tangible medium, having stored thereon instructions that cause a computing system to execute a method for shifting a load between two or more access points in a wireless network, the instructions comprising:
instructions to receive a request for a communication session between a first wireless access point and a mobile device, wherein the request includes an access class and the load is determined for the access class on the first wireless access point;
instructions to receive a RF utilization and a signal strength;
instructions to determine a load on at least the first wireless access point;
based on the RF utilization, the signal strength, and the load, instructions to move the requested communication session to a second wireless access point;
instructions to determine if there is less load on the second wireless access point for the access class;
if there is less load on the second wireless access point for the access class, send a signal to the first wireless access point to instruct the mobile device to communicate with the second wireless access point for the communication session; and
if there is more load on the second wireless access point for the access class, send a signal to the first wireless access point to admit the communication session.
10. The non-transitory computer readable medium as defined in claim 9 , after admitting the communication session, the instructions further comprising:
instructions to receive an event;
instructions to determine the event;
based on the event, instructions to determine if a load needs shifting;
if the load does not need shifting, maintaining a configuration of the first and second wireless access points;
if the load needs shifting, determining a load on the first wireless access point and the second wireless access point;
if the load on the second wireless access point is greater, shifting load from the second wireless access point to the first wireless access point; and
if the load on the first wireless access point is greater, shifting load from the first wireless access point to the second wireless access point.
11. The non-transitory computer readable medium as defined in claim 9 , wherein the instructions to determine if load needs shifting further comprises weighting the RF utilization or the signal strength to determine which wireless access points should receive more load.
12. The non-transitory computer readable medium as defined in claim 11 , wherein the RF utilization is weighted more during high loads.
13. The non-transitory computer readable medium as defined in claim 11 , wherein the signal strength is weighted more during low loads.
14. A communication system comprising:
two or more wireless access points, the two or more wireless access points configured to measure a radio frequency (RF) utilization and a signal strength and configured to communicate with at least one mobile device, wherein a communication with the at least one mobile device represents a load on one of two or more wireless access points; and
a control server in communication with the two or more wireless access points, the control server configured to receive the RF utilization, the signal strength, and an amount of load from each of the two or more wireless access points, configured to weigh the measured RF utilization or the measured signal strength more than other factors and, depending on the amount of load on the two or more wireless access points, and based on the weighted values of the measured RF utilization and the measured signal strength, configured to shift a load from a first wireless access point to a second wireless access point.
15. The communication system as defined in claim 14 , wherein each of the two or more wireless access points comprises:
a traffic measurements module configured to measure the RF utilization and the load; and
a signal interface module configured to measure the signal strength.
16. The communication system as defined in claim 14 , wherein the control server comprises a load balance module configured to determine a load and to shift the load.