doc.: IEEE /0080r0 Submission January 2013 Yongho Seok, LG ElectronicsSlide 1 Backoff Procedure in RAW Date: Authors: NameAffiliationsAddressPhone Yongho SeokLG Electronics LG R&D Complex Anyang-Shi, Kyungki- Do, Korea Minyoung ParkIntelHillsboro, OR Matthew Jinsoo ChoiLG Electronics Jeongki KimLG Electronics Hangyu ChoLG Electronics Eric WongBroadcomSunnyvale, CA Tom TetzlaffIntel Emily QiIntel Simone MerlinQualcommSan Diego, CA Amin JafarianQualcomm Bin TianQualcomm Santosh AbrahamQualcomm Menzo WentinkQualcomm Hemanth SampathQualcomm VK jonesQualcomm
doc.: IEEE /0080r0 SubmissionSlide 2 NameAffiliationsAddressPhone Hongyuan ZhangMarvell Sudhir SrinivasaMarvell George CalcevHuaweiRolling Meadows, IL, USA m Osama Aboul MagdHuawei Young Hoon KwonHuawei Betty ZhaoHuawei David YangxunHuawei Bin ZhenHuawei ChaoChun WangMediaTek James WangMediaTek Jianhan LiuMediaTek Vish PonnampalamMediaTek James YeeMediaTek Huai-Rong Shao Samsung Electronics Chiu NgoSamsung Electronics Minho CheongETRI Jae Seung LeeETRI Hyoungjin KwonETRI Jaewoo ParkETRI Sok-kyu LeeETRI Sun, Bo ZTE Lv, Kaiying ZTE Authors: Yongho Seok, LG Electronics January 2013
doc.: IEEE /0080r0 SubmissionYongho Seok, LG ElectronicsSlide 3 Authors: NameAffiliationsAddressPhone Sayantan ChoudhuryNokia Klaus DopplerNokia Chittabrata GhoshNokia Esa TuomaalaNokia Ken MoriPanasonic Rojan ChitrakarPanasonic Haiguang WangI2R Shoukang ZhengI2R Yeow Wai LeongI2R Zander LeiI2R Jaya ShankarI2R Anh Tuan HoangI2R Joseph Teo Chee MingI2R Anna PantelidouRenesas Mobile Juho PirskanenRenesas Mobile Timo KoskelaRenesas Mobile Liwen ChuSTMicroelectronics George VlantisSTMicroelectronics January 2013
doc.: IEEE /0080r0 Submission Introduction In this presentation, we propose a backoff procedure in RAW. Background of RAW –A Restricted Access Window (RAW) is divided in time slots. –STA wakes up at TBTT and it listens to a Beacon frame that indicates the slot duration for each Restricted Access Window (RAW). Slot duration for each RAW may be different –STA determines its channel access slot assigned by AP. –STA may sleep before its channel access slot. –STA shall start to access the channel at the slot boundary of its channel access slot based on EDCA. –AP indicates a Cross Boundary Option applied in each RAW: If it is set to False, a TXOP or transmission within a TXOP shall not extend across a slot boundary January 2013 Yongho Seok, LG ElectronicsSlide 4
doc.: IEEE /0080r0 Submission Introduction If STA in power save mode has a pending MPDU, it can transmit the pending MPDU anytime under the EDCA access method. Otherwise, it wakes up at TBTT and it listens to a Beacon frame whose TIM indicates that the AP does not have any BUs buffered for this STA. AP assigns to each STA/group-of-STA a channel access slot at which the STA is allowed to contend inside RAW –AP can provide the different backoff parameter for RAW January 2013 Yongho Seok, LG ElectronicsSlide 5
doc.: IEEE /0080r0 Submission Backoff Procedure in RAW The following backoff function states are defined –Backoff function state outside RAW (1 st Backoff function state) –Backoff function state inside RAW (2 nd Backoff function state) January 2013 Yongho Seok, LG ElectronicsSlide 6 Beacon Restricted Access Window 1 st Backoff function state 2 nd Backoff function state TXOP procedure 2 nd Backoff function state TXOP procedure 1 st Backoff function state AP STA1 STA2 STA1 has a pending MPDU Slot 0Slot 1 Doze StateActive State
doc.: IEEE /0080r0 Submission Backoff Procedure in RAW STA suspends backoff at the start of a RAW and stores the backoff function state January 2013 Yongho Seok, LG ElectronicsSlide 7 Beacon Restricted Access Window AP STA1 STA1 has a pending MPDU Slot 0Slot st Backoff function is suspended inside RAW 1 st Backoff function states (e.g., Backoff timer and CW) are stored
doc.: IEEE /0080r0 Submission Backoff Procedure in RAW At the end of RAW, the previously stored backoff function state is restored and the backoff function resumes –If the previously stored backoff function state is empty, STA invokes a backoff procedure January 2013 Yongho Seok, LG ElectronicsSlide 8 Beacon Restricted Access Window AP STA1 STA1 has a pending MPDU Slot 0Slot TXOP procedure 1 st Backoff function states are restored 1 st Backoff function resumes outside RAW
doc.: IEEE /0080r0 Submission Backoff Procedure in RAW If STA is participating in the RAW, STA invokes a new backoff function using the RAW backoff parameters January 2013 Yongho Seok, LG ElectronicsSlide 9 Beacon Restricted Access Window TXOP procedure AP STA1 STA2 STA1 has a pending MPDU Slot 0Slot 1 Doze StateActive State TXOP procedure nd Backoff function uses RAW backoff parameters
doc.: IEEE /0080r0 Submission Backoff Procedure in RAW STA may count down backoff only in its assigned slots within the RAW unless cross boundary is set to true, in which case the STA may continue to count down backoff after its slot January 2013 Yongho Seok, LG ElectronicsSlide 10 Beacon Restricted Access Window AP STA1 STA2 Slot 0Slot 1 Doze StateActive State TXOP procedure 4321 Doze StateActive State When Cross boundary is set to false
doc.: IEEE /0080r0 Submission Backoff Procedure in RAW STA may count down backoff only in its assigned slots within the RAW unless cross boundary is set to true, in which case the STA may continue to count down backoff after its slot January 2013 Yongho Seok, LG ElectronicsSlide 11 Beacon Restricted Access Window AP STA1 STA2 Slot 0Slot 1 Doze StateActive State TXOP procedure 4321 Doze StateActive State TXOP procedure When Cross boundary is set to true
doc.: IEEE /0080r0 Submission Conclusion We propose a backoff procedure in a Restricted Access Window. Because AP can overwrite the default backoff parameters for operation inside RAW, it may need to define two backoff function states. Then, we propose how two backoff function states are processed. LG Electronics Slide 12
doc.: IEEE /0080r0 Submission Straw Poll Do you support the following backoff procedure in RAW? –STA suspends backoff at the start of a RAW and stores the backoff function state –If STA is participating in the RAW, STA invokes a new backoff function using the RAW backoff parameters STA may count down backoff only in its assigned slots within the RAW unless cross boundary is set to true, in which case the STA may continue to count down backoff after its slot –When the RAW ends, the previously stored backoff function state is restored and the backoff function resumes January 2013 Yongho Seok, LG ElectronicsSlide 13