1. Method for geting Link RCPI
September 2007
doc.: IEEE /2376r0
May 2008
Method for geting Link RCPI
Date:
Authors:
Notice: This document has been prepared to assist IEEE It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.
Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE
Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures < ieee802.org/guides/bylaws/sb-bylaws.pdf>, including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE Working Group. If you have questions, contact the IEEE Patent Committee Administrator at
Junling Hu
Steve Emeott, Motorola

2. September 2007
doc.: IEEE /2376r0
May 2008
Abstract
This submission is about how to get the RCPI for switching path with the peer station when the peer station is working in PS mode.
Junling Hu
Steve Emeott, Motorola

3. September 2007
doc.: IEEE /2376r0
May 2008
Background
In current z draft 1.0, Link_RCPI_Request/Report primitives have been defined for measuring and getting Link RCPI.
Link_RCPI_Request/Report are transmitted directly between the STAs
Junling Hu
Steve Emeott, Motorola

4. May 2008
Problem
When a station directly sends the Link_RCPI_Request message to the peer station before the station wants to switch the link to direct path from AP path or before the station just tries to setup a direct link, the peer station may be failed to receive the message if it is just in PS mode.
Junling Hu

5. May 2008
Use Case
For a 2Mbps video stream between two STAs in a BSS, it occupies 4% time to send or receive for each STA. So each STA can sleep at least on MAC level in 96% time in theory and they both work in PSM.
STA1(stream receiver) finds AP path is not good enough to support the QoS required by the stream service( e.g. delay, Jitter because the AP has a heavy traffic or data lost because the air interference, but the average throughput is still high enough to support both STAs to work in PSM ), it tries to setup DL with STA2 or switch from AP path to DL path(if the DL has been setup already). STA1 wants to get RCPIs of STA2 firest, but STA2 is in PSM. AP
1. Collecting a 100ms video stream data, and transmitting the 100ms video data for about 4ms, During the 96ms of each 100ms, the STA can be in idle state in theory, at least on MAC level.
3. Receiving a 100ms video stream data for 4ms, sleeping for 96ms of each 100ms in theory.
2. AP transfers the 100ms video stream data for about another 4ms
STA1(in PSM)
STA2(in PSM)
Junling Hu

6. May 2008
Solution （1/2）
Two new messages RCPI_Syn_Request/Response are added to awake the peer STA and make synchronization with the initiator STA.
After awaking the peer STA, then the Link_RCPI_Request/Response procedure happends
Junling Hu

7. Solution （2/2） The procedure can be described as below. May 2008
① STA1 sends RCPI_Syn_Request through AP path through the tunnel ( if STA1 is in power saving mode, it keep in temporary awake state ).
② After receiving RCPI_Syn_Request, STA2 sends RCPI_Syn_Response directly and keep in temporal awake state.
③ After receiving RCPI_Syn_Response, STA1 sends Link_RCPI_Request to STA2 directly.
④ After receiving Link_RCPI_Request, STA2 sends Link_RCPI_Report to STA1 and then go to doze state. AP
① RCPI_Syn_Request
Data
② RCPI_Syn_Response
③ Link_RCPI_Request
STA1
STA2
④ Link_RCPI_Report
Junling Hu

8. May 2008
Straw poll
Do you think we should solve the problem indicated in 11-08/0304r2?
-Yes No Abstain
Do you agree the method to solve this problem?
Junling Hu

9. May 2008
END
Junling Hu