Simulation for EDCF Enhancement Comparison November 2002 doc.: IEEE 802.11-02/xxxr0 January 2003 Simulation for EDCF Enhancement Comparison Isaac Lim Wei Lih Matsushita Electric Ind. Isaac Lim, Matsushita Electric Ind. Menzo Wentink, Intersil Corp.

EDCF Enhancement Simple Queue Control for EDCF January 2003 EDCF Enhancement Simple Queue Control for EDCF Station contend for an EDCF TXOP when the MAC transmission queue size is greater than a specified limit Use EDCF TXOP more effectively Reduce the numbers of collisions Queue size limit depends on traffic requirement Isaac Lim, Matsushita Electric Ind.

Case 1: Simulation Scenario January 2003 Case 1: Simulation Scenario Four 6Mbps streams transmitted using Block Ack mechanism at 36Mbps OFDM PHY with 10% PER TXOP Limit = 3msec MSDU Size = 1402 Bytes Block Ack Request control frame is generated after 8 data frames being transmitted. Case 1a – Normal EDCF: AIFS = DFIS, CWmin = 15, CWmax = 1023 Case 1b – Simple Queue Control Queue Size Limit = 8 MSDUs AIFS = DIFS, CWmin = 15, CWmax = 1023 Isaac Lim, Matsushita Electric Ind.

Bandwidth Utilization January 2003 Bandwidth Utilization Normal EDCF EDCF with Simple Queue Control Isaac Lim, Matsushita Electric Ind.

End-to-End Delay January 2003 Case 1a Case 1b Isaac Lim, Matsushita Electric Ind.

Detail Results November 2002 doc.: IEEE 802.11-02/xxxr0 January 2003 Parameter Settings Data Rate = 6Mbps No of source STA = 4 Type of ACK = Block ACK (8) Nominal MSDU size = 1402 bytes Delay Bound = 64TU PER = 10% Case Limit Mean ETE Delay (sec) S.D. ETE Delay (sec) MSDU Dropped MSDU Transmitted STA1 STA2 STA3 STA4 1a – No Control - 0.007817 0.003219 19, 76 8, 18 5, 21 19, 111 315675 1b – Queue Control 8 data frames 0.015208 0.003110 3, 20 3, 18 3, 21 7, 41 SER refers to Slot Error Rate. PER refers to Packet Error Rate. PI refers to Polling Interval. MSDU received with end-to-end delay > delay bound MSDU dropped by transmitter due to exceed delay bound Isaac Lim, Matsushita Electric Ind. Menzo Wentink, Intersil Corp.

Case 2: Simulation Scenario January 2003 Case 2: Simulation Scenario Same setting as in Case 1 with 1Mbps background traffic being added to each scenario. 10 background traffic generator with each is having data rate @ 100Kbps to be transmitted using legacy setting Isaac Lim, Matsushita Electric Ind.

End-to-End Delay January 2003 Case 2a Case 2b Isaac Lim, Matsushita Electric Ind.

Throughput for Background Traffic January 2003 Throughput for Background Traffic Case 2a Average Throughput = 952228 bps Case 2b: Average Throughput = 976814 bps Isaac Lim, Matsushita Electric Ind.

Results with background traffic November 2002 doc.: IEEE 802.11-02/xxxr0 January 2003 Results with background traffic Parameter Settings Data Rate = 6Mbps No of source STA = 4 Type of ACK = Block ACK (8) Nominal MSDU size = 1402 bytes Delay Bound = 64TU PER = 10% Case Limit Mean ETE Delay (sec) S.D. ETE Delay (sec) MSDU Dropped MSDU Transmitted STA1 STA2 STA3 STA4 2a – No Control - 0.022016 0.019124 3207, 19693 3014, 17657 3076, 18176 2584, 15425 315675 2b – Queue Control 8 data frames 0.019317 0.006305 280, 1246 313, 1568 241, 1033 271, 1160 SER refers to Slot Error Rate. PER refers to Packet Error Rate. PI refers to Polling Interval. MSDU received with end-to-end delay > delay bound MSDU dropped by transmitter due to exceed delay bound Isaac Lim, Matsushita Electric Ind. Menzo Wentink, Intersil Corp.

Conclusion Simple Queue Control Simple to Implement January 2003 Conclusion Simple Queue Control Simple to Implement Can be implementation Specific Bandwidth usage reduction is caused by the reduction in collisions. Distributed in nature Each stream can determine it’s own queue size limit base on it’s own traffic requirement in order to yield better results Fail to operate when network is overloaded Need a Bandwidth Resource Controller to prevent network to be overloaded Isaac Lim, Matsushita Electric Ind.