Ad Hoc无线网络公平调度算法研究

Research on Fair Scheduling Algorithms in Ad Hoc Wireless Networks

随着个人通信的日益增长,支持诸如移动会议、移动网络以及自然灾难营救的ad hoc无线网络逐渐从军用扩大到商用等诸多领域。商用ad hoc无线网使用一种称为“付费使用”(pay-for-use)的模式,于是在用户间定义合理的公平机制则变得非常重要。公平机制的核心问题是公平调度算法问题。但是在ad hoc无线网中,公平分配带宽和最大化利用资源本质上是冲突的,这为公平调度算法的设计带来了巨大的挑战。本文系统地研完了著名的公平性标准以及两类公平调度机制。通过模拟和分析,我们讨论了这两类公平调度机制中存在的问题。此外,我们提出了一种新的公平调度模型并给出了模拟结果。模拟结果表明,该算法在公平性和带宽利用率之间实现了理想的平衡。

With the increase of personal communications, ad hoc wireless networks that are able to provide a wide range of network applications are spreading from military areas to lots of commercial areas. Commercial ad hoc wireless networks use a pay-for-use mode, so a reasonable fairness mechanism is required among users. The core problem of fairness mechanism is fair scheduling algorithms. However, in ad hoc wireless networks fair distribution of band-width and maximization of resource utilization are in conflict in nature, which brings us a great challenge for designing fair scheduling algorithms. In this paper, we systematically investigate the well-known fairness norms and two kinds of fair scheduling mechanisms. Through simulation and analysis results, we discuss the limitations of these two scheduling mechanisms. Furthermore, we propose a new fair scheduling model and present the simulations. The simulation results show that our fair scheduling mode achieves satisfactory balance between fairness and maximization of bandwidth utilization.