1. Supporting Authentication/Association for Large Number of Stations
Month Year
doc.: IEEE yy/xxxxr0
January 2012
Supporting Authentication/Association for Large Number of Stations
Date:
Authors:
Haiguang Wang et. al, I2R, Singapore
John Doe, Some Company

2. Month Year
doc.: IEEE yy/xxxxr0
January 2012
Abstract
In this contribution, we present the performance of current Authentication/Association protocols for networks with large number of nodes. We found that it is necessary to limit the number of stations that can perform the authentication/association simultaneously.
Haiguang Wang et. al, I2R, Singapore
John Doe, Some Company

3. January 2012
Motivation
IEEE ah is required to support up to 6000 stations by a single AP. It is necessary to examine performance of existing standard in supporting large number of nodes, including authentication/association.
Haiguang Wang et. al, I2R, Singapore

4. January 2012
Usage Scenarios
In smart grid application, when AP or stations experience power outage, the stations may try to authenticate/associate with AP simultaneously after recovery. The AP is required to handle a sudden burst of authentication/association requests from a few thousands stations within a short period.
Haiguang Wang et. al, I2R, Singapore

5. Authentication/Association Procedure
January 2012
Authentication/Association Procedure
Haiguang Wang et. al, I2R, Singapore

6. Simulation Parameters
January 2012
Simulation Parameters
Simulator
Qualnet network simulator
Simulation parameters
DCF mode
With implemented Authentication/Association protocol.
Basic parameters
Parameter
Value
Data Rate
1 Mbps
Backoff Win
Number of Nodes
Maximum Short Retry 7
DIFS
50 us
Maximum long Retry 4
SIFS
10 us
Time slot
20 us
Haiguang Wang et. al, I2R, Singapore

7. January 2012
Topology
Haiguang Wang et. al, I2R, Singapore

8. Month Year
doc.: IEEE yy/0112r0
Performance Results for Authentication/Association of Stations within 200 Seconds Limit
Haiguang Wang et. al, I2R, Singapore
Haiguang Wang et. al, I2R, Singapore

9. January 2012
Suggested Solution
Limit the number of stations that can authenticate/associate with AP at the same time.
Make use of the last byte of station’s MAC address to limit the number of stations.
AP broadcast a value V in the beacon.
Stations with last byte of MAC address less than V are allowed to send authentication request.
AP can adjust the value of V to control the number of stations performing authentication/association process.
Haiguang Wang et. al, I2R, Singapore

10. Performance Results by Limiting Number of Stations
January 2012
Performance Results by Limiting Number of Stations
Haiguang Wang et. al, I2R, Singapore

11. January 2012
Conclusions
Simulation results show that, it is necessary to control the number of stations performing authentication/association at the same time to improve the performance in scenario with large number of stations.
Haiguang Wang et. al, I2R, Singapore

12. January 2012
References
[1] Chao-Chun Wang, “Supporting Large Number of STAs in ah”, IEEE /1019, July 2011
Haiguang Wang et. al, I2R, Singapore

13. January 2012
Straw Poll (1)
Do you agree that AP should limit the number of stations to be authenticated/associated at the same time? Y: N: A:
Haiguang Wang et. al, I2R, Singapore

14. January 2012
Straw Poll (2)
Do you agree to use MAC address to limit the number of stations to be authenticated/associated at the same time? Y: N: A:
Haiguang Wang et. al, I2R, Singapore