实现多无线接入点网络连接模型的研究

本文提出一种负载均衡模型,此模型不仅考虑AP的信号强度,而且要考虑现有AP已接入无线工作站的数量还有连接质量因素。除此之外,还讨论了实现此模型的无线协议的扩充。     

浅析虚拟现实技术中系统场景漫游实现

虚拟场景技术是虚拟现实系统的重要组成部分,如何在三维虚拟场景中实现实时漫游,这是系统良好交互性的基础。该文从系统学的观点出发对虚拟现实技术中的系统场景漫游进行了分析和论述,并浅析了虚拟场景漫游系统构建的基本方法。     

无线局域网中的信息安全保护和安全漫游

在描述无线局域网中现有安全机制的基础上,提出了一个比较全面的信息安全保护和安全漫游解决方案。采用RADIUS和ESSID认证、MAC地址过滤、WEP加密并动态生成WEP密钥(128位加密密钥)等机制,来保护用户数据的私密性;采用基于MobileIP和RADIUS协议的漫游机制来支持用户在多个接入点之间的漫游,保证用户在进行安全漫游时不中断业务。     

用户的候鸟效应对移动通信网络的冲击

随着经济和社会的发展,人们的流动性越来越强,运营商的用户、移动终端也在同步漫游迁移。在3G时代,由于智能终端的大量普及和用户使用习惯的改变,这种大规模的用户迁移对网络产生了较大的冲击。深入分析了候鸟用户的组成和使用习惯,聚焦于农民工和学生2个候鸟用户群体,并通过中国联通2个地（市）春节前后网络数据的对比,得出了候鸟用户对人口流出城市和人口流入城市移动通信网络的不同影响,并提出了运营商的应对策略,即网络建设中充分考虑漫游用户数量,修正用户预测模型,在人口流入地区与人口流出地区采用灵活的资源共享机制。     

GSM蜂窝无线通信系统

ＧＳＭ数字移动通信系统是现今较先进的一种无线通信系统，本文对该系统的组成特点、功能原理、信令系统和帧结构，以及今后的发展等作了较详细的介绍，以飨读者。     

应用于移动环境中的WLAN接入网结构

文章介绍了把无线局域网接入与GSM,GPRS漫游融合在一起的运营无线局域网(OWLAN),分析了OWLAN的主要系统单元及功能,讨论了基于用户识别模块(SIM)的鉴权、漫游和计费机理。     

A secure authentication and billing architecture for wireless mesh networks

Wireless mesh networks (WMNs) are gaining growing interest as a promising technology for ubiquitous high-speed network access. While much effort has been made to address issues at physical, data link, and network layers, little attention has been paid to the security aspect central to the realistic deployment of WMNs. We propose UPASS, the first known secure authentication and billing architecture for large-scale WMNs. UPASS features a novel user-broker-operator trust model built upon the conventional certificate-based cryptography and the emerging ID-based cryptography. Based on the trust model, each user is furnished with a universal pass whereby to realize seamless roaming across WMN domains and get ubiquitous network access. In UPASS, the incontestable billing of mobile users is fulfilled through a lightweight realtime micropayment protocol built on the combination of digital signature and one-way hash-chain techniques. Compared to conventional solutions relying on a home-foreign-domain concept, UPASS eliminates the need for establishing bilateral roaming agreements and having realtime interactions between potentially numerous WMN operators. Our UPASS is shown to be secure and lightweight, and thus can be a practical and effective solution for future large-scale WMNs. Yanchao Zhang received the B.E. degree in Computer Communications from Nanjing University of Posts and Telecommunications, Nanjing, China, in July 1999, and the M.E. degree in Computer Applications from Beijing University of Posts and Telecommunications, Beijing, China, in April 2002. Since September 2002, he has been working towards the Ph.D. degree in the Department of Electrical and Computer Engineering at the University of Florida, Gainesville, Florida, USA. His research interests are network and distributed system security, wireless networking, and mobile computing, with emphasis on mobile ad hoc networks, wireless sensor networks, wireless mesh networks, and heterogeneous wired/wireless networks. Yuguang Fang received the BS and MS degrees in Mathematics from Qufu Normal University, Qufu, Shandong, China, in 1984 and 1987, respectively, a Ph.D degree in Systems and Control Engineering from Department of Systems, Control and Industrial Engineering at Case Western Reserve University, Cleveland, Ohio, in January 1994, and a Ph.D degree in Electrical Engineering from Department of Electrical and Computer Engineering at Boston University, Massachusetts, in May 1997. From 1987 to 1988, he held research and teaching position in both Department of Mathematics and the Institute of Automation at Qufu Normal University. From September 1989 to December 1993, he was a teaching/research assistant in Department of Systems, Control and Industrial Engineering at Case Western Reserve University, where he held a research associate position from January 1994 to May 1994. He held a post-doctoral position in Department of Electrical and Computer Engineering at Boston University from June 1994 to August 1995. From September 1995 to May 1997, he was a research assistant in Department of Electrical and Computer Engineering at Boston University. From June 1997 to July 1998, he was a Visiting Assistant Professor in Department of Electrical Engineering at the University of Texas at Dallas. From July 1998 to May 2000, he was an Assistant Professor in the Department of Electrical and Computer Engineering at New Jersey Institute of Technology, Newark, New Jersey. In May 2000, he joined the Department of Electrical and Computer Engineering at University of Florida, Gainesville, Florida, where he got early promotion to Associate Professor with tenure in August 2003, and to Full Professor in August 2005. His research interests span many areas including wireless networks, mobile computing, mobile communications, wireless security, automatic control, and neural networks. He has published over one hundred and fifty (150) papers in refereed professional journals and conferences. He received the National Science Foundation Faculty Early Career Award in 2001 and the Office of Naval Research Young Investigator Award in 2002. He also received the 2001 CAST Academic Award. He is listed in Marquis Who’s Who in Science and Engineering, Who’s Who in America and Who’s Who in World. Dr. Fang has actively engaged in many professional activities. He is a senior member of the IEEE and a member of the ACM. He is an Editor for IEEE Transactions on Communications, an Editor for IEEE Transactions on Wireless Communications, an Editor for IEEE Transactions on Mobile Computing, an Editor for ACM Wireless Networks, and an Editor for IEEE Wireless Communications. He was an Editor for IEEE Journal on Selected Areas in Communications: Wireless Communications Series, an Area Editor for ACM Mobile Computing and Communications Review, an Editor for Wiley International Journal on Wireless Communications and Mobile Computing, and Feature Editor for Scanning the Literature in IEEE Personal Communications. He has also actively involved with many professional conferences such as ACM MobiCom’02 (Committee Co-Chair for Student Travel Award), MobiCom’01, IEEE INFOCOM’06, INFOCOM’05 (Vice-Chair for Technical Program Committee), INFOCOM’04, INFOCOM’03, INFOCOM’00, INFOCOM’98, IEEE WCNC’04, WCNC’02, WCNC’00 (Technical Program Vice-Chair), WCNC’99, IEEE Globecom’04 (Symposium Co-Chair), Globecom’02, and International Conference on Computer Communications and Networking (IC3N) (Technical Program Vice-Chair).     

基于Mobile IP的WLAN/GPRS融合网络

首先比较了WLAN和GPRS两种技术的特点；接着提出了一种基于Mobile IP的支持WLAN/GPRS网络无缝漫游的融合方案，它利用WLAN网络与GPRS网络在技术上的互补性，可快速为用户提供支持无缝漫游的数据业务。此方案基于如下基本思想：尽量不对GPRS网络做任何修改，而主要通过对对WLAN网络结构进行调整来实现两者的融合。在描述此方案的主要工作流程时，包括以下方面的内容：移动接点接入/附着、WLAN到GPRS的漫游，GPRS到WLAN的漫游、WLAN网络可用性的判断、计费等。     

游牧精神与建筑文化探索

现代西方人的先祖都是来自草原的游牧民族,游牧基因没有在其后的历史发展中消亡,反而在新的时代被再次激活并焕发光彩。基于此,该文致力探索古希腊建筑与规划设计中体现出的游牧精神,并由此联系到对希腊精神产生共鸣的现代主义设计（主要分析勒·柯布西埃的作品）,进而延续到对于当代具有游牧精神的前卫设计,简洁梳理出一条游牧哲学在西方建筑史中发展的脉络,企图从游牧文化的角度重新思考建筑的意义,并希望对当代建筑设计有所启迪。     

5G无线网共享建设方案

随着5G网络的商用和大规模部署,5G设备单站成本高、站址需求大、功耗高等问题成为运营商5G网络建设和运营中的巨大挑战。在国家网络强国战略和提速降费的要求下,运营商需要探索新的网络建设和运营模式,在保障5G网络高质量建设的基础上提升5G网络的效益和资产运行效率,网络共建共享模式成为电信运营商5G运营新模式。从网络共享技术方案分析入手,分析了异网漫游和接入网络共享技术方案,结合中国联通和中国电信5G网络共享,分析了接入网共享下NSA网络共享方案和SA演进方案。