doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 1 Simulation Results for p-DCF, v-DCF and Legacy DCF Khaled Turki, Jin-Meng Ho, Sid Schrum, Matthew Shoemake and Don Shaver Texas Instruments Inc.

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 2 Simulation Environment Simulation platform: OPNET MAC schemes simulated: 1.p-DCF as described in 00/467r1 2.v-DCF as described in 00/412 and 01/

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 3 Parameters Buffer size = 2 Mbits Packet lifetime = 500 ms Retry limit = 7 PHY = 11 Mbps- DSSS

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 4 Scenarios 20 STA 10 STA Bi-directional streams Packet length = 1500 bytes and 500 bytes Packet length distribution : Constant Arrival process : Exponential inter-arrival times

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 5 Contention-Based Access: CSMA with Persistent Contention -- State Transition Diagram ESTA active Medium idle for DIFS or EIFS? Calculate PP Yes Any TCPP changed? Transmission permitted? (X PP?) Transmit a frame Contention continued? Stop Slot idle? Recalculate PP No Yes No Yes No

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 6 Simulation Results- 20 STA

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 7 Simulation Results p-DCF, v-DCF and STA -Arrival Rate =~ 6 Mbps

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 8 Simulation Results (p-DCF) 20 STA -Arrival Rate =~ 6 Mbps In this simulation run, error is added to calculated PP. Error margins are 15% and 20 %.

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 9 Simulation Results (p-DCF) 20 STA -Arrival Rate =~ 6 Mbps

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 10 Simulation Results (v-DCF) Delay vs. Retries 20 STA Aggregate data arrival rate =~ 6 Mbps CO=10 CW_min=63

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 11 Simulation Results (v-DCF) 20 STA Arrival rate =~ 6 Mbps CO=10 CW_min=15

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 12 Simulation Results (v-DCF) Back-off Techniques 20 STA Aggregate data arrival rate =~ 6 Mbps CO=10 CW_min=15 New formula = Back-off doubles after first retry

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 13 Simulation Results -- Set 2

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 14 Simulation Results (v-DCF and p-DCF) 20 STA Aggregate data arrival rate =~ 2 Mbps CO=10 CW_min=63 and p-DCF Packet length = 500 bytes

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 15 Simulation Results – Set 3 (v-DCF and p-DCF) 10 STA Aggregate data arrival rate =~ 3 Mbps CO=10 CW_min=63 and p-DCF

doc.: IEEE /037 Submission January 2001 Khaled Turki et. al,Texas InstrumentsSlide 16 Conclusions Several simulations have been performed in order to evaluate the performance of two EDCF proposals (v-DCF and p-DCF) The probabilistic approach shows performance superiority over v-DCF at higher loads and large STA population. –Delay and delay variance –Dropped frame rate –Stability in terms of frame delay