1. Station Group Management for 802.11ah
Month Year
doc.: IEEE yy/xxxxr0
Station Group Management for ah
Date: May 10, 2011
Author:
Name
Company
Address
Phone
Jonghyun Park
LG Electronics
LG R&D Complex 533, Hogye-1dong, Dongan-gu, Anyang-shi, Kyungki-do, Korea
John Doe, Some Company

2. Accelerate Contribution
November 2009
Accelerate Contribution
Abstract
This contribution addresses
One of potential MAC change issues regarding “high STA density per BSS”
The need of STA group management, related mainly to IEEE ah Use Case 1 – Sensors and meters
LG Electronics, Inc.

3. Accelerate Contribution
November 2009
Accelerate Contribution
Motivation
Possibility of a significant large number of STAs per AP [2]
Smart grid – meter to pole (6,000 STAs per AP)
Environmental / agricultural monitoring ( <300 STAs per AP)
Industrial process sensors ( STAs per AP)
One BSS vs. Multiple BSSs per AP
To manage “Thousands of STAs”
LG Electronics, Inc.

4. Need for STA Group Management
November 2009
Accelerate Contribution
Need for STA Group Management
In general,
It may be manageable to control a large number of STAs,
based on unique/similar characteristics of ah STAs, e.g.,
Short / infrequent / periodic traffic at large time intervals
However, in some event-based/bursty traffic situations,
“Thousands of STAs” may contend at the same time
 The likelihood of uplink collisions goes up
LG Electronics, Inc.

5. Accelerate Contribution
November 2009
Accelerate Contribution
STA Group Management
Group-wise STA management using multiple BSSID
Each BSSID is assigned to a specific group of STAs
AP can operate BSSID-specific contention periods
to avoid a massive collision from a large number of contending STAs from other groups at the same time
LG Electronics, Inc.

6. Accelerate Contribution
November 2009
Accelerate Contribution
STA Grouping
Example of STA grouping with multiple BSSIDs
Location based
Application type based
LG Electronics, Inc.

7. Comparison with Deploying Multiple APs
November 2009
Accelerate Contribution
Comparison with Deploying Multiple APs
Pros of Multiple APs
No enhanced MAC (and PHY) functionalities are required
Cons of Multiple APs
Additional AP deployment cost
Collision issues may remain unresolved due to increased OBSS problem
Assuming limited number of available channels (e.g., 917 – MHz in Korea)
Limited control of STA coordination across APs
LG Electronics, Inc.

8. Accelerate Contribution
November 2009
Accelerate Contribution
Conclusion
Group-wise STA management using multiple BSSID is desirable, regarding “high STA density” issues for IEEE802.11ah.
Station group management mechanisms should be further discussed.
LG Electronics, Inc.

9. References
[1] IEEE P Wireless LANs, IEEE ah Call for proposals, IEEE /0198r0
[2] IEEE P Wireless LANs, Potential Compromise for ah Use Case Document, IEEE /0457r0
[3] IEEE P Wireless LANs, TGah STA Analysis for Smart Grid Use Case, IEEE /0355r0
[4] IEEE P Wireless LANs, Association ID management for TGah, IEEE /0088r0
[5] IEEE P Wireless LANs, Sub 1 GHz license-exempt MAC areas to consider, IEEE /1045r0