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Enhancement for AV Transmission. Lim Wei Lih, Yasuo HARADA , Shinichiro OHMI , Tan Pek Yew (Matsushita Electric Ind.). Outline. TXOP Improvement QoS Registration Delay-ACK Duplication History. TXOP Improvement. TXOP Improvement. Objectives High efficiency
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Enhancement for AV Transmission Lim Wei Lih, Yasuo HARADA, Shinichiro OHMI, Tan Pek Yew (Matsushita Electric Ind.) Lim Wei Lih, Matsushita Electric Ind.
Outline • TXOP Improvement • QoS Registration • Delay-ACK Duplication History Lim Wei Lih, Matsushita Electric Ind.
TXOP Improvement Lim Wei Lih, Matsushita Electric Ind.
TXOP Improvement • Objectives • High efficiency • Deliver Delay-ACK during TXOP • Means • The earlier ending of a TXOP is known by the gap. • The end of Data’s TXOP is PIFS. • The end of Delay-ACK’s TXOP is DIFS. Lim Wei Lih, Matsushita Electric Ind.
Initial TXOP1 (for Data) Next TXOP Data Domain Polling Polling QoS Data QoS Data Delay-Ack QoS Data QoS Data QoS Data QoS Data QoS Data SIFS PIFS DIFS SIFS SIFS SIFS SIFS SIFS SIFS SIFS TXOP Improvement Scheme Lim Wei Lih, Matsushita Electric Ind.
QoS Registration Lim Wei Lih, Matsushita Electric Ind.
QoS Registration • 2-phase TXOP allocations in HCF • TXOP with Registrations • TXOP allocations w/o Registrations Lim Wei Lih, Matsushita Electric Ind.
Beacon Beacon Allocation Structure Repeat k times Repeat j times 0..1 time Repeat i times 0..1 time 0..1 time QoS Request Registration QoS TXOP Allocation TXOP Allocation PIFS PIFS PIFS PIFS TBTT TBTT DIFS Phase 2 : TXOP w/o Registration Phase 1 : TXOP with Registration Contention Base Contention Free Period Lim Wei Lih, Matsushita Electric Ind.
Phase 1 • TXOP with Registration • Registration • Using Controlled Contention for ESTN to indicate intention • Protect Registration Information frame by granting TXOP • QoS TXOP Allocation • Only for ESTA with successful QoS Registration • Allocating TXOPs by using polling (CF-Poll/CF-Multipoll) • QoS registration given EAP/HC knowledge of QoS requests – better and more efficient scheduling Lim Wei Lih, Matsushita Electric Ind.
TXOP For Station 4 (QoS Request frames) TXOP For Station 8 (QoS Request frames) TXOP For Station 2 (QoS Request frames) Acknowledgement EAP/HC Poll Stn 2 CC (Feedback) EAP/HC Poll Stn 8 RR RR RR CC (Initialization) EAP/HC Poll Stn 4 PIFS SIFS PIFS PIFS SIFS PIFS SIFS PIFS SIFS PIFS Phase 1 – QoS Request Registration QoS Request Registration Illustration Lim Wei Lih, Matsushita Electric Ind.
TXOP For Station 4 TXOP For Station 8 TXOP For Station 2 EAP/HC Poll Stn 2 EAP/HC Poll Stn 4 EAP/HC Poll Stn 8 SIFS PIFS SIFS PIFS SIFS Phase 1 – QoS TXOP Allocation QoS TXOP Allocation Illustration Lim Wei Lih, Matsushita Electric Ind.
Phase 2 • TXOP w/o Registration • Perform Polling based on • Error Statistics information element • QoS Control field • QoS data frame • Null QoS data frame • Own queues status • RR frames • Reservation Request Policy • Performing Controlled contention • Giving ESTA chances to indicate request Lim Wei Lih, Matsushita Electric Ind.
Delay-ACK Duplication History Lim Wei Lih, Matsushita Electric Ind.
Delay-ACK with Duplicated history • Loss of information from a Delay-ACK can be recovered from next coming Delay-ACK Lim Wei Lih, Matsushita Electric Ind.
Duplication History Lim Wei Lih, Matsushita Electric Ind.