A contention-free 802-11 protocol for multi-WLAN configurations

The authors developed the CFPSM protocol (Vimal, K. et al., IEEE TENCON, 2003) that enhanced the IEEE 802.11 ad-hoc WLAN protocol. CFPSM enables contention-free transmissions between STAs (stations) in an ad-hoc WLAN, after an initial channel reservation period. We used NS-2 simulations to show that CFPSM has 1/6 of the power consumption and 25% higher throughput than the standard 802.11 protocol. We now present extensions to CFPSM for multi-WLAN configurations to support mobile ad-hoc routing. The suggested mechanisms lead to optimal frame transmissions across adjacent WLANs and avoid problems like indefinite postponement of transmissions or wastage of contention-free periods in WLANs.