Performance Analysis of Wireless Local Area Networks
M. U. Naru, Umar Nauman, Khalid Hussain · International Journal of Computer Theory and Engineering · 2009
In an infrastructure based wireless network, access point (AP) is the central authority which controls all the registered nodes and relaying traffic in the network.Even though all traffic is routed through AP, the open nature of the underlying medium is prone to environmental factors, etc. which degrade the performance of the overall network.However, in a saturated case the AP becomes the bone of contention among nodes which can result in collisions, packet drops, etc.In this study, authors analyze the performance of 802.11WLANs that utilizes the Distributed Coordination Function (DCF).A simulation study having contending stations within the transmission range of an AP in a saturated environment are considered, in view of varying data rates and packet sizes in an error free environment.Simulation results are presented and analyzed in the end. I. INTRODUCTION:There have been many developments in the field of networking in past decade but the most important one was the development of wireless networks that provides ease of feasibility to roam around.Wireless networks have been given a lot of attention because of its flexible nature in the data communication systems.It has been implemented as an extension or as an alternative of wired networks, which can be deployed virtually anywhere; from offices to university campus or providing hotspots at the airports, cafes, etc.Besides having many advantages, wireless networks have some limitations as well which are generally due to the underlying medium being used.These limitations involve mobility, fewer battery life, frequent collisions and limited bandwidth.Such factors degrade the overall network performance [1].Many researchers have tried to increase the performance.To achieve this, many models were proposed to improve the performance by increasing the throughput and decreasing the delay, especially in a dense environment.Few of them achieved the desirable performance metrics with low delay and high throughput but most of them lack these desirable performance metrics.The analysis of 802.11CSMA/CA was first conducted by [2] to calculate the throughput in a saturated environment.Thereafter, many enhancements have been proposed in this area like Markov Chain model to incorporate retransmission without using the backoff process [3], to minimize the complexity and computation time the Markov chain model is reduced from two dimensions to one [4], etc.Another variation has been the calculation of packet drops probability, delay, etc. to analyze CSMA/CA based wireless network's