基于用户需求的自治无线网络协作模型与优化机制研究

Wireless networks have seen a rapid growth in the past decade, thanks to the widespread adoption of smart phones, 3G cellular network infrastructure, and home wireless routers. Currently, wireless (WiFi) networks are the primary network access technology at home, with each AP supporting multiple wireless devices such as smart phones, smart pads, and laptops. However, the current deployment of residential wireless networks are autonomous, dense, and chaotic in that each home deploys its own home wireless routers without any coordination with other homes in the same building. As a result, the home wireless performance in residential buildings is often unsatisfying to the users, because the interference between neighboring wireless networks can be severe. The interference will only become worse as home wireless APs become the hubs of the smart home electronics such as TV, setup-box, smart refrigerator, air conditioner etc. Therefore, the current autonomous and chaotic home wireless network deployment cannot meet the demand of the current and future growth of Mobile Internet and Internet of Things (IoT). To address above challenges, in this project we propose a cooperation model for autonomous home wireless networks based on user demand. Such a model can be used in other wireless environments such as office buildings for small business. The project plans to clearly define the cooperation model, in which user performance is measured and quantified, and the wireless resources are coordinated among neighboring APs to achieve better overall performance. This project will first study the severity of the interference of autonomous home wireless networks, the variety of the user demand, challenges of performance measurement. Then we propose a gaming theory model and an optimization model with appropriate constraints, based on user demand. Furthermore, we propose design guidelines and a assessment framework for the cooperation model. Based on above guidelines and framework, we design reference architecture, which, without scarifying user privacy, monitors home wireless environment, troubleshoots performance degrade, analyzes high-level user behavior, and optimizes overall network performance. Finally, based on above architecture, we build an actual system on top of open-sourced home router operating system OpenWrt, an centralized coordinator, and standard API between OpenWrt software and the coordinator. We plan to evaluate our system's performance with a testbed of hundreds of home wireless routers running our software. We plan to lease our codes to the open source community so that the proposed architecture can be more widely adapted and benefit the growth of mobile Internet and IoT.

随着国家出台"宽带中国"和"智慧城市"等相关文件，未来家用无线网络迅速发展，为用户提供灵活多样的无线应用。目前大部分无线网络无序部署，各自自治管理，已成为抑制用户性能的主要因素。本项目提出以满足用户需求为主要目的的自治网络协作模型，通过量化用户性能需求，协调用户无线资源，达到用户性能的共同提高。首先，本项目以现有家用无线网络为基础，总结现有的无线网络自治管理，干扰严重，用户需求多样，性能评估困难等特点，探索自治无线网络协作的基本要素。其次，基于博弈论和最优化理论提出协作优化目标和相关约束，提出自治无线网络协作模型的设计原则和性能评价体系。最后，基于OpenWrt实验平台，分析现有家用无线网络基本要素，提出一种自治无线网络协作参考模型，在保证用户隐私安全的条件下，实现无线网络的无线环境监测，性能下降根因分析，用户行为特点分析和网络性能优化。

国家“宽带中国”和“智慧城市”相关文件的下发和移动互联网的快速发展，自治家用无线网络得到了极大的普及。本项目通过搭建OpenWrt实验平台和真实部署自治无线网络到居民网络等方法，测量发现现有的无线网络由于无序部署、自治管理，高密度等原因，导致干扰严重，无线时延大、吞吐低等问题。本项目首先提出了使用的自治无线网络测量和检测的使用方法，通过大量的网络行为数据进行大数据分析，对性能下降的原因进行根因分析，并结合机器学习决策树进行了相应的优化。其次，本项目提出了自治无线网络干扰测量的方法，能够在不需要借助企业级设备的前提下测量自治无线网络各实体之间的干扰图，并以此作为输入，利用最优化理论探索自治无线网络协同的方法。通过实验床相关实验，改方法能够显著降低自治无线网络各实体的实验。再次，本项目进一步追本溯源，指出自治无线网络之间干扰严重其核心是因为无线网络协议CSMA/CA机制的缺陷，本项目提出一种对时延友好的协议，能够在不降低吞吐率的情况下，更好的保证各无线实体之间的公平性，防止干扰者无限制占用信道，以此达到降低时延的目的。最后，本项目针对自治无线网络中用户隐私的保护也做了探索，指出了自治无线网络中存在的安全隐患，提出了易用的测量工具，帮助自治无线网络用户尽早发现安全隐患并加以防范。所以本项目从理论到实践，从测量、分析到优化，从协议、实体、内容，用户等多个交叉维度进行了研究工作，旨在基于用户需求，对自治无线网络进行全方位的测量和优化。