The MAC performance of IEEE 802.11 DCF and the IEEE 802.11e EDCA is analyzed in nonsaturated condition which means sometimes the device does not have a packet for transmission. In this paper we assume that there is no generation of flow while the previous flow is in service and the number of packets in flow is geometrically distributed. In the non-saturated condition, the first packet arriving ...

This paper analyzes the impact of misbehaviour on QoS provisioning in wireless mesh networks. Misbehaviour occurs when a network participant decides not to cooperate. Since cooperation is fundamental for distributed environments such as mesh networks, misbehaviour can be a serious threat to them. In this work, the authors focus on the IEEE 802.11 EDCA medium access function which provides QoS i...

Wireless Local Area Networks (WLANs) are one of the fastest growing wireless access technologies. The IEEE 802.11 Standard doesn’t support any QoS mechanisms. IEEE 802.11 MAC layer supports two basic access mechanisms, DCF (Distributed Coordination Function) and PCF (Point Coordination Function). The EDCA mechanism of the IEEE 802.11e standard provides QoS support through service differentiatio...

In this paper, we propose an analytical model for the performance evaluation of IEEE 802.11e enhanced distributed channel access (EDCA). Different from most previous analytical studies based on the saturation assumption, we extend the analytical model to non-saturation conditions. An empty state is introduced into the Markov chain to represent the status of transmission queue being empty. This ...

In this paper, we present a model to analyze the throughput and delay performance of the EDCA mechanism under non saturation conditions. The main strength of our model is that it can be used to analyze generic source models, as it neither makes any assumption on the source’s arrival process nor requires all packets be of the same length. Simulation results confirm the accuracy of our model unde...

Network collision is a known problem in CSMA/CA networks. This work presents a new solution to mitigate the issue of network collision. Our solution is fundamentally different from traditional random backoff methods in that a station can reasonably reuse a time slot in consecutive backoff cycles to achieve resource reservation. This solution can be readily used to enhance 802.11 DCF/EDCA with m...

We focus on performance analysis of IEEE 802.11e EDCA in non-saturation condition. There have not been many analytic works in non-saturation condition due to mainly analytic complexity of models. However, non-saturation is valid in most real WLAN network. In this paper, we deal with the non-saturation case that the flow is not generated during which the previous flow is in service and flow size...