1. Simulation Results for Controlled Contention Mechanism
November 2001
doc.: IEEE /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

2. 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.

3. 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.

4. Results Note: Average Duration Time shown is in s
November 2001
doc.: IEEE /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