IEEE 802.11 DCF Improvement: Waiting DIFS while Waiting Back-off
Latifa Souad Mahi-Rekik et. al. · International Journal of Computing and Digital Systems · 2018
With the emergence of time-sensitive applications such as games and telephony, the introduction of the Quality of Service (QoS) in general and the improvement of transmission delays in particular have become a must in wireless networks.The distributed coordination function (DCF) being the fundamental access method and the basis of the wireless LANs IEEE 802.11MAC protocol, a great number of works have been done to improve it.In DCF, after sensing an idle channel, stations have to wait before the transmission of each frame a length of time called DIFS (DCF Inter Frame Space) followed by another called back-off.If the medium becomes busy during the back-off process, the back-off timer is paused and resumed when the medium is sensed free for a DIFS again.This time loss becomes considerable when the number of interruptions of back-off process grows.This paper proposes a contribution to improve DCF by combining IFS and back-off time.The simulation results show that the approach benefits are proportional to the contention level of the network and to the number of hops in multi-hop network topologies.