Novel medium control for wireless networks: providing total QoS and energy conservation

Nowadays, wireless network users demand support for different types of traffic combined with longer battery lifetime for their mobile devices. This work proposes a new medium control for wireless LANs as an alternative to the HCF (hybrid coordination function) scheme defined by the IEEE 802.11e workgroup. LEPOHA (low energy priority oriented hybrid access) is a complete medium access mechanism, it integrates a polling based and a TDMA access scheme, which are both power saving capable, provides QoS for all types of traffic, adapts to the changing conditions of modern WLANs, optimizes channel utilization and station feedback, provides medium contention fairness, exhibits zero collisions, employs priorities to differentiate traffic, provides dynamic resource assignment, and instantly negotiates the quality levels of the offered traffic streams trying to support multiple streams with best possible quality. Furthermore, it introduces a complete power saving scheme, which causes no performance degradation. LEPOHA, compared with HCF, exhibits generally superior performance and clearly lower energy consumption.