EDCF TXOP Bursting Simulation Results Month 1998 doc.: IEEE 802.11-98/xxx January 2002 EDCF TXOP Bursting Simulation Results Javier del Prado and Sunghyun Choi Philips Research USA Briarcliff Manor, New York sunghyun.choi@philips.com S. Choi, Philips

References IEEE 802.11e QoS draft D2.0 January 2002 References IEEE 802.11e QoS draft D2.0 IEEE 802.11-01/566r3: “Multiple Frame Exchanges during EDCF TXOP” S. Choi, Philips

January 2002 Problem Statement Per 802.11e/D2.0, QSTA cannot transmit multiple MSDUs within an EDCF TXOP Why not? As showed in 01/566r3, EDCF TXOP bursting has some advantages while adding minimum complexity S. Choi, Philips

Advantages of EDCF TXOP Bursting January 2002 Advantages of EDCF TXOP Bursting Reduce network overhead: Without bursting available, a QSTA must backoff after each MSDU transmission Multiple transmissions using SIFS Burst Acknowledgement can be used Bandwidth fairness among the same priority queues, independent from the frame sizes The HCF polled access is not affected since the EDCF TXOP is limited by the “CP TXOP limit” determined by the HC S. Choi, Philips

Simulation scenario Fixed data rate of 11 Mbps January 2002 Simulation scenario Fixed data rate of 11 Mbps 8 QSTAs: 4 voice QSTAs, 4 video QSTAs Traffic pattern: S. Choi, Philips

Simulation scenario I EDCF parameters: January 2002 Simulation scenario I EDCF parameters: Simulations for different TXOP lengths S. Choi, Philips

Simulation results I Global Throughput No Bursting 3.5 ms 5 ms January 2002 Simulation results I Global Throughput 2 frames of video per TXOP 3 frames of video per TXOP No Bursting 3.5 ms 5 ms S. Choi, Philips

Simulation results I Global Data Dropped No Bursting 3.5 ms 5 ms January 2002 Simulation results I Global Data Dropped No Bursting 3.5 ms 5 ms S. Choi, Philips

Simulation results I Delay Voice No Bursting 3.5 ms 5 ms January 2002 S. Choi, Philips

Simulation results I Delay Video No Bursting 3.5 ms 5 ms January 2002 S. Choi, Philips

Simulation results I Throughput video streams No Bursting 3.5 ms 5 ms January 2002 Simulation results I Throughput video streams No Bursting 3.5 ms 5 ms S. Choi, Philips

Simulation scenario II January 2002 Simulation scenario II EDCF parameters: S. Choi, Philips

Simulation results II Global Throughput 3.5 ms 5 ms January 2002 Simulation results II Global Throughput 3 frames of video per TXOP 2 frames of video per TXOP 3.5 ms 5 ms S. Choi, Philips

Simulation results II Data Dropped 3.5 ms 5 ms January 2002 S. Choi, Philips

Simulation results II Delay Voice 3.5 ms 5 ms January 2002 S. Choi, Philips

Simulation results II Delay Video 3.5 ms 5 ms January 2002 S. Choi, Philips

Simulation scenario III January 2002 Simulation scenario III 6 QSTAs, 1 priority Traffic patterns: 3 QSTAs for each set of traffic pattern Network overloaded S. Choi, Philips

Simulation results III January 2002 Simulation results III Throughput - No Bursting Video 1 Video 2 S. Choi, Philips

Simulation results III January 2002 Simulation results III Throughput - 7 ms TXOP Video 1 Video 2 S. Choi, Philips

January 2002 Conclusions EDCF TXOP Bursting increases global throughput when the network is highly loaded It reduces the global delay It may increase the delay of streams with low load. This delay can be reduced by adapting the EDCF parameters (as shown in scenario II) Provides bandwidth fairness among queues with the same priority and different frame sizes (as shown in scenario III) S. Choi, Philips

January 2002 Conclusions II In general, we observe a better performance in scenario II in terms of throughput and delay due to a lower probability of collision between QSTAs The HCF polled access performance should not be affected since the HC controls the duration of the EDCF TXOP Minimum complexity added optionally as EDCF TXOP bursting will be optional ! S. Choi, Philips