Scheduling for next generation WLANs: filling the gap between offered and observed data rates

In wireless networks, opportunistic scheduling is used to increase system throughput by exploiting multi-user diversity. Although recent advances have increased physical layer data rates supported in wireless local area networks (WLANs), actual throughput realized are significantly lower due to overhead. Accordingly, the frame aggregation concept is used in next generation WLANs to improve efficiency. However, with frame aggregation, traditional opportunistic schemes are no longer optimal. In this paper, we propose schedulers that take queue and channel conditions into account jointly, to maximize throughput observed at the users for next generation WLANs. We also extend this work to design two schedulers that perform block scheduling for maximizing network throughput over multiple transmission sequences. For these schedulers, which make decisions over long time durations, we model the system using queueing theory and determine users' temporal access proportions according to this model. Through detailed simulations, we show that all our proposed algorithms offer significant throughput improvement, better fairness, and much lower delay compared with traditional opportunistic schedulers, facilitating the practical use of the evolving standard for next generation wireless networks

Study and Analysis of Performance of IEEE 802.11 Power Saving Mode

The nodes need to be turned into low-power states when they are not in use to conserve energy and power for battery- powered wireless devices. One of the most important techniques in wireless LAN and multi-hop wireless networks is the IEEE 802.11 power saving mode which is used to coordinate the power states of communication devices [1]. Energy performance and bandwidth resource limitations are the backbone of any ad hoc network design. Multi-rate adaptation architectures had been proposed to increase bandwidth utilization efficiency and to reduce the control overhead [4]. Simulations were performed in order to see how specific parameters influence the performance of the power saving mechanism for the wireless Local Area Networks in IEEE 802.11. Simulations were made for an ad hoc-network with 25 stations. The throughput were obtained for specific window size and beacon interval and then an optimal ratio between ATIM window interval and beacon interval is recommended. It is found that the ratio between ATIM window interval and beacon interval should be between 30 to 40 percent

Optimization of The use of Wireless Lan Devices to Minimize Operational Costs

WLAN technology has been widely developed for the needs of internet access in people's lives. Several generations of WLAN technology include IEEE 802.11b, IEEE 802.11a, IEEE 802.11g and IEEE 802.11n. At the STAHN Rectorate Building, Gde Pudja Mataram, WLAN technology in its application requires financial consideration because excessive use of Internet Service Provider services results in a waste of operational costs. The application of WLAN is still not optimal, because there are not too many users, but the operational costs of implementing the local wireless network are very large, due to less optimal application of network infrastructure. The recommended WLAN technology is IEEE 802.11n, while the technology is the latest technology that has better quality than the previous generation technology. The research methodology uses the Network Development Life Cycle (NDLC). Of the 6 stages available, only 3 stages are used, namely Analysis, Design and Simulation of Prototyping. The results obtained from this study are models that design a WLAN that suits your needs, and complements the entire Building area.  Optimization has succeeded in reducing the need for ISP and client services while still being able to enjoy services as needed and cost optimization can be reduced by around 28%

Modelling and Evaluation of 60 GHz IEEE 802.11 Wireless Local Area Networks in ns-3

In this thesis we present modifications made to the popular network simulation environment ns-3 to provide accurate simulation of IEEE 802.11ad Wireless Local Area Networks (WLANs) in the 60 GHz band. There is a need for such a framework as it allows research into how a directional, high performance wireless link affects various parts of the networking stack and Medium Access Control (MAC) design. The work contained herein describes changes made to the existing WLAN MAC and Physical Layer (PHY) model in ns-3 to support antenna directionality and multi-Gbps throughput. The resulting model is then analysed and found to accurately match optimal theoretical values in a number oftest scenarios. The result of this work is a simulation model capable of emulating IEEE 802.11ad WLANs with correct MAC and PHY representations