Simulation Results for Controlled Contention Mechanism November 2001 doc.: IEEE 802.11-01/XXXr0 November 2001 Simulation Results for Controlled Contention Mechanism Yasuo HARADA, Pek Yew Tan, Wei Lih Lim Matsushita Electric Ind. Presented by: S. Kandala, Sharp Labs Y. Herada et. al. Srinivas Kandala, Sharp Labs

Controlled Contention November 2001 Controlled Contention AP initiate controlled contention by sending out CC frame which indicate the number of RR slots that are being allocated On upon receiving CC frame, station determine a RR slot for transmission Controlled Contention can effectively reduce the number of stations contending for RR slots by specifying criteria. An efficient method for station to indicate TXOP request Y. Herada et. al.

Simulation Aim Scenarios November 2001 Simulation Aim Measure the time duration taken for X number of stations to successfully transmit a frame with MSDU size = 1880 bytes to AP at 36Mbps, where X = 5, 10, 20 & 50 Scenarios Case 1: Using only CSMA/CA Case 2: Controlled Contention (RR slots = No of stations associated with AP) followed by CSMA/CA Case 3: Controlled Contention (RR slots = 2 * No of stations associated with AP) followed by CSMA/CA Y. Herada et. al.

Results Note: Average Duration Time shown is in s November 2001 doc.: IEEE 802.11-01/XXXr0 November 2001 Results Note: Average Duration Time shown is in s Retry Counter for CSMA/CA is set to unlimited CCOP = 440 s (time duration to transmit a frame with size = 1880 bytes at 36Mbps OFDM) Case 2 and Case 3 will produce better result if controlled contention is initiated more than once. Cases that starting with Controlled contention reduce the number of stations contending before normal transmission. Y. Herada et. al. Srinivas Kandala, Sharp Labs