نتایج جستجو برای: تابع edca

تعداد نتایج: 21474  

2016
Najwan Khambari Bogdan V. Ghita David Lancaster Lingfen Sun

This paper proposes a set of performance enhancements techniques aiming to improve the perceived performance of video transmission across the IEEE 802.11e network. The proposed mechanism preserves the video Quality of Experience (QoE) by protecting the I-Frames transmitted as part of the Group of Pictures (GoP) during queue congestion. The method is evaluated using the NS-3 simulator with the E...

2009
Mohamad El Masri Guy Juanole Slim Abdellatif

We propose in this paper a Markov chain model that describes the behavior of an EDCA (Enhanced Distributed Channel Access) access category under saturation. Compared to previous work [1], [2], [3], the model explicitly integrates the behavior of an access category when submitted to a virtual collision. We give in this paper two views of the model : a general one explicitly representing the diff...

2014
S. Udayabaskaran Reni Sagayaraj

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 ...

2009
Szymon Szott Marek Natkaniec Albert Banchs

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...

2012
Ravi Gorripati V. VenkataRamana Chenna Reddy

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...

2006
ZHANG Wei SUN Jun LIU Jing ZHANG Hai-bin

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 ...

Journal: :Wireless Personal Communications 2007
Pablo Serrano Albert Banchs Arturo Azcorra

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...

2009
Yong He Ruixi Yuan Jie Sun Weibo Gong

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...

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