Be-Ozr: An Efficient Available Bandwidth Estimation In Ieee802.11E Network

In wireless network, the support for Quality of Service (QoS) depends on the ability of a network to estimate the available bandwidth of a link effectively and efficiently. Due to the shared nature of the wireless medium, there has been challenges in achieving an accurate measurement of the available bandwidth. This paper therefore proposes an efficient available bandwidth estimation approach that improves the accuracy of previously proposed approach for accurate measurement. The approach used in this paper is to passively estimate the available bandwidth, where the maximum range of the channel idle time measurement used in the calculation is re-defined to address the outer zone range threshold (OZR). This limits the under-estimation and over-estimation of bandwidth measurement. The proposed approach used limits the network overhead and achieves accuracy and efficiency. Results obtained from the simulation shows how our proposed approach out-performs the state-of the-art approach in terms of throughput and delay, using the IEEE802.11e. We have been able to achieve 8% improvement in accuracy and efficiency when compared with the best of the state-of-the-art available bandwidth estimation technique.

MODIFIED PASSIVE AVAILABLE BANDWIDTH ESTIMATION IN IEEE 802.11 WLAN

Quality of Service provisioning for real-time multimedia applications is largely determined by a network’s available bandwidth. Until now, there is no standard method for estimating bandwidth on wireless networks. Therefore, in this study, a mathematical model called Modified Passive Available Bandwidth Estimation (MPABE) was developed to estimate the available bandwidth passively on a Distributed Coordination Function (DCF) wireless network on the IEEE 802.11 protocol. The mathematical model developed was a modification of three existing mathematical models, namely Available Bandwidth Estimation (ABE), Cognitive Passive Estimation of Available Bandwidth V2 (cPEAB-V2), and Passive Available Bandwidth Estimation (PABE). The proposed mathematical model gave emphasis on what will be faced to estimate available bandwidth and will help in building strategies to estimate available bandwidth on IEEE 802.11. The developed mathematical model consisted of idle period synchronisation between sender and receiver, the overhead probability occurring in the Medium Access Control (MAC) layer, as well as the successful packet transmission probability. Successful packet transmission was influenced by three variables, namely the packet collision probability caused by a number of neighbouring nodes, the packet collision probability caused by traffic from hidden nodes, and the packet error probability. The proposed mathematical model was tested by comparing it with other relevant mathematical models. The performance of the four mathematical models was compared with the actual bandwidth. Using a series of experiments that have been performed, it was found that the proposed mathematical model is approximately 26% more accurate than ABE, 36% more accurate than cPEABV2, and 32% more accurate than PABE.