An efficient data burst transmission mechanism for wireless LANs

In this paper, we present a data burst transmission mechanism named data flushing data transfer (DFDT) protocol for IEEE 802.11 wireless local area network (WLAN). The basic mechanism of DFDT is quite the same as the distributed coordination function (DCF) of the medium access control (MAC) of IEEE 802.11, which uses a random access delay backoff time after a busy medium condition and request-to-send/clear-to-send (RTS/ CTS) dialogue before sending actual payload data (direct data/ACK could also be used). The enhancement introduced by DFDT is mainly produced by the compilation process (CP), which fits as many MAC layer frames as possible into one physical layer frame within the limit of a predetermined length. Compiling several data frames into one data frame before transmission can obviously reduce the contention overheads. Moreover, DFDT allows a station to send out multiple MSDUs destined for different receivers with one physical data frame after a successful contention. By using the CP, we lower the protocol overhead, the packet arrival rate of the physical layer, and network contention all with one action. The proposed DFDT takes the advantages of the RTS/CTS mechanism relative to traditional IEEE 802.11 protocol but has less the overhead. Simulation results backed by numerical analysis show growing improvement in performance, limited by the saturation of the network, as the network load gets higher.