网捷网络全新的集成WLAN解决方案

美国网捷网络公司参加了2004年10月26-30日在北京举行的中国国际通信设备技术展，向参观者充分展示了公司在效交换和路由领域领先的技术和产品．包括：NelIron 40G (IPv4／IPv6万兆以太网路由器)、BigIron MG8(万兆以太网第三层交换机)、Fasdron Edge X系列交换机、Servedron GT E高可用性应用和流量管理交换机、IronPoim200无线接入点等。     

组建基于“海蜘蛛”和接入点的中小无线局域网

介绍了利用海蜘蛛（Hi—spider）软路由和AP（接入点）组建无线局域网,并且通过软路由的PPPoE（以太网上点到点协议）功能实现对接入用户的可控管理。     

MIPv6中的移动网络技术

侧重讨论在MIPv6中的移动网络与Internet主机通信时数据包路由定向所产生的问题。移动网络是指劝态变换接入点的网络。IETF建议的关于移动节点的MIPv6谇不能有效支持移动网络，缺乏较好的可扩展性，并且引入了一些安全认证问题，在此提出了一种网络前缀绑定与多插技术解决方案。     

嵌套移动网络路由优化代价分析模型的创建

在现代社会中,人们通信过程中的设备与无线传感器种类也越来越丰富,对于获得信息的需求也在逐渐改变,互联网连接模式中的固定终端与单一化移动终端已经无法使实际需求得到满足,在关联设备群中进行移动。此多个无线终端设备共同移动,会使互联网接入点改变,创建稳定移动体,也就是网络移动性。为了解决嵌套移动网络中的路由优化与数据包多层封装的问题,提出嵌套移动网络路由优化分析模型。     

基于SGWM的230 MHz无线宽带通信技术的用电信息采集系统的通信系统设计

用电信息采集系统是建设智能电网的重要内容.针对用电信息采集系统中现有230MHz无线专网存在的通信速率低、接入点较少、采集成功率不高、实时性较差的问题,提出了基于SGWM的230 MHz无线宽带通信技术的用电信息采集系统的通信系统的技术方案及其功能实现,分析了载波聚合复用、智能路由、异频组网等通信组网技术,阐述了SGWM无线通信技术在用电信息采集系统的应用.对组网方案的设计及分析表明,基于SGWM的230 MHz无线宽带通信技术在用电信息采集系统的应用效果较好,为推广应用信息双向交互和加快推进智能电网建设提供了技术支撑.     

双DSP技术在无线分组网络路由控制器中的应用

文章介绍了双DSP技术在无线分组网络路由控制器中的应用。详细阐述了双DSP间通信方案的选择及双DSP系统的实现 ,提出了一种双DSP对多个串行通信控制器 (SCC)的设计方案 ,并给出了具体的硬件、软件设计方法。     

军用通信网络路由技术研究

首先对军用通信网络组成、结构和特征进行了分析,给出了军用通信网络部分总体性能指标和定义,定性分析了这些性能指标对网络路由的影响。然后,通过对军用通信网络路由优化准则的研究,给出了军用通信网络路由模型的一般形式,分析了路由优化与流量控制、带宽分配和频率指配等网络管理的关系。为深入进行军用通信网络路由优化和网络管理的研究提供了分析依据。     

通信IP网BFD应用的研究

通信IP网作为实时业务传输载体,要求能够对相邻系统之间通信故障进行快速检测,在出现故障时可以快速切换到备份链路,以保证实时数据不间断传输。在研究BFD协议原理的基础上,根据通信IP网运行中出现的问题,应用BFD双向快速检测功能,实现了VRRP的Master/Backup状态毫秒级切换,并利用BFD会话检测静态路由所在链路的状态,实现一跳和多跳的静态路由自动切换,提高了通信IP网的可靠性。     

影响无线通信未来的几项关键技术

用户和路由设备可以在网络中随机移动的即必（Ad hoe）网已经成为目前一个重要的研究领域，这种新兴技术可在突发情况下进行方便地通信。传统无线网络中的网络接入点一般是固定接入到宽带主干网上，而且对数据速率的要求越来越高，例如IEEE802．11a/g要求54Mbps的数据速率。为此，许多新技术应运而生．并将对无线通信领域产生重大影响。     

用波分复用技术设计和实现的双波长光纤环网

本文设计和实现了具有PCI总线峰值带宽传输能力的光互连网络接口卡。采用可编程门阵列实现硬件路由和同步流水线传输以减小数据包在网络中的通信延迟。为扩展网络规模,采用波分复用技术实现了双波长环网。通过无源光学器件实现双波长信号和合波和分束,通过探测器选择接收不同波长的光信号以实现波长路由。该网络结构扩展为多波长环网。     

Full-duplex wireless information and power transfer in two-way relaying networks with self-energy recycling

Wireless Networks - In this paper, we consider full-duplex (FD) two-way relaying networks, where wireless power transfers from hybrid power access-point, H to user and wireless information...     

中继增强型蜂窝网络接入选择策略的研究

主要考虑中继接入选择策略对基于OFDMA的中继增强型蜂窝网络带来的系统性能影响.分别针对集中式和分布式控制两种情景,以最大化用户吞吐量为目标设计了基于信干噪比的接入选择策略.并通过搭建基于802.16j的系统级动态仿真平台对其性能进行仿真分析.与传统的接入方案相比.该方案在用户吞吐量分布,以及不同中继位置下的系统频谱效率指标下,均可获得更好的系统性能增益.     

Handover keying and its uses

Mobile nodes must authenticate themselves in order to use network services. When mobile nodes roam into a new cell, they must re-authenticate to the new layer 2 and 3 devices. This re-authentication process can take as long as two seconds, which is unacceptable for applications such as voice over IP. In this article we present several recently developed authentication protocols that can reduce the reauthentication delay. Both intra-domain and inter-domain handover scenarios are discussed. We mainly focus on two protocols ? 802.11r and EAP Re-authentication Protocol for handover keying. These two protocols use security key hierarchies to avoid full authentication. An application of these protocols is presented for the control and provisioning of a wireless access-point network.     

Dynamic Reconfigurable WDM 60-GHz Millimeter-Waveband Radio-Over-Fiber Access Network: Architectural Considerations and Experiment

We will propose a dynamic reconfigurable wavelength-division-multiplexed (WDM) millimeter-waveband (mm-waveband) radio-over-fiber (RoF) access network and demonstrate, for the first time, a dynamic-channel-allocation capability of millimeter-waveband optical RoF signals in WDM access network using a supercontinuum light source, arrayed-waveguide gratings, and a reconfigurable optical-crossconnect switch. The dynamic reconfigurable RoF network architecture is presented, and its features are described. Then, four 155-Mb/s RoF channels are effectively generated, transmitted through 25 km of fiber, switched, transmitted again through 2 km of fiber, and detected with an error-free operation (bit error rate < 10^-10). The proposed RoF architecture is highly scalable, both in terms of channel and access-point counts.     

Facilitation of consumer loyalty toward branded applications: The dual-route perspective

Although many brands develop mobile applications (apps) to build relationships with consumers, most branded apps fail to retain consumers’ loyalty. This study examines the facilitation of consumer loyalty toward branded apps (continuance intention, in-app purchase intention, and word-of-mouth intention) from the dual-route perspective. One route is the affective (relationship) route, where brand benefits (functional benefits, experiential benefits, symbolic benefits, and monetary benefits) drive parasocial interactions between consumers and the brand, which, in turn, influences branded app loyalty. The other route is the utility route, where system characteristics (system quality and information quality) affect perceived usefulness, which, in turn, facilitates branded app loyalty. An online survey was conducted, and the research model was empirically tested using partial least squares structural equation modeling. The findings support the dual-route perspective according to which both affective and utilitarian paths facilitate branded app loyalty. The key theoretical contribution of this study is that it moves beyond the utilitarian path and finds the affective (relationship) path to give a more complete picture of the facilitation of consumer loyalty in the branded app context. A strategy is provided to suggest to practitioners how to design branded apps to facilitate consumer loyalty.     

信令网MAP业务过程双路由问题分析报告

移动网络随着竞争的需要和移动互联网的发展,原有CS业务网络也逐步向IP化方向发展。目前,信令网络中存在由LSTP／HSTP点组成的E1信令链路网和NGN软交换组成的IP路由、本文对移动网中存在的双路由业务情况进行了深入的分析说明,对于信令网维护人员有一定参考价值,对提高信令监测系统数据的完整性有促进作用。     

Special Photoconverter

A special device with photocurrent amplification function is reported.The device with long base region structure consists of dual-route photodetectors and their amplifier.Two photodetectors with a space of 50μm are precisely located in this device.The dvice with current snesitivity of S≥ 15A/lm,static state current transmission coefficient of hFE≥5000,single-route dark current of ID≥1μA,high frequency current transmission coefficient modulus of |hfe|≥1 at 400MHz is obtained.At present,the device has been tried out in some inertia systems.     

Multiple-route current-voltage (I-V) characteristics of GaAs-InGaAsmetal-insulator-semiconductor-like (MIS) structure for multiple-valuedlogic applications

A new GaAs-In_xGa_1-xAs metal-insulator-semiconductor-like (MIS) device with the interesting dual-route and multiple-negative-differential-resistance (MNDR) current-voltage (I-V) characteristics has been fabricated and demonstrated. These performances are caused by the successive barrier lowering and potential redistribution effect. A novel multiple-route I-V characteristic is obtained in the studied device at low temperature (-130°C). This performance is different from the previously reported NDR switching device and has not yet been found in other devices. The interesting property of the studied structure provides a promising candidate for switching device applications     

高速光纤综合通信网络平台研究

现代通信网络应能满足各种通信业务和通信容量日益发展的需求,实现话音、数据、视频、IP等业务的一体化综合交换和传输。在比较TDM、IP和ATM三种协议的基础上,提出"采用内置RPR和MPLS功能的MSTP平台"建设光纤综合通信网络平台的实现方法。MSTP采用SDH的数据帧结构,保持了SDH标准光接口、灵活分插低速信号、自愈环保护和功能强大的网管等优点,可对TDM、IP和ATM协议进行优化传输。     

Alternative Schemes for Dynamic Secure VPN Deployment in UMTS

Three alternative schemes for secure Virtual Private Network (VPN) deployment over the Universal Mobile Telecommunication System (UMTS) are proposed and analyzed. The proposed schemes enable a mobile node to voluntarily establish an IPsec-based secure channel to a private network. The alternative schemes differ in the location where the IPsec functionality is placed within the UMTS network architecture (mobile node, access network, and UMTS network border), depending on the employed security model, and whether data in transit are ever in clear-text, or available to be tapped by outsiders. The provided levels of privacy in the deployed VPN schemes, as well as the employed authentication models are examined. An analysis in terms of cost, complexity, and performance overhead that each method imposes to the underlying network architecture, as well as to the mobile devices is presented. The level of system reliability and scalability in granting security services is presented. The VPN management, usability, and trusted relations, as well as their behavior when a mobile user moves are analyzed. The use of special applications that require access to encapsulated data traffic is explored. Finally, an overall comparison of the proposed schemes from the security and operation point of view summarizes their relative performance. Christos Xenakis received his B.Sc. degree in computer science in 1993 and his M.Sc. degree in telecommunication and computer networks in 1996, both from the Department of Informatics and Telecommunications, University of Athens, Greece. In 2004 he received his Ph.D. from the University of Athens (Department of Informatics and Telecommunications). From 1998–2000 was with the Greek telecoms system development firm Teletel S.A., where was involved in the design and development of advanced telecommunications subsystems for ISDN, ATM, GSM, and GPRS. Since 1996 he has been a member of the Communication Networks Laboratory of the University of Athens. He has participated in numerous projects realized in the context of EU Programs (ACTS, ESPRIT, IST). His research interests are in the field of mobile/wireless networks, security and distributed network management. He is the author of over 15 papers in the above areas. Lazaros Merakos received the Diploma in electrical and mechanical engineering from the National Technical University of Athens, Greece, in 1978, and the M.S. and Ph.D. degrees in electrical engineering from the State University of New York, Buffalo, in 1981 and 1984, respectively. From 1983 to 1986, he was on the faculty of Electrical Engineering and Computer Science at the University of Connecticut, Storrs. From 1986 to 1994 he was on the faculty of the Electrical and Computer Engineering Department at Northeastern University, Boston, MA. During the period 1993–1994 he served as Director of the Communications and Digital Processing Research Center at Northeastern University. During the summers of 1990 and 1991, he was a Visiting Scientist at the IBM T. J. Watson Research Center, Yorktown Heights, NY. In 1994, he joined the faculty of the University of Athens, Athens, Greece, where he is presently a Professor in the Department of Informatics and Telecommunications, and Director of the Communication Networks Laboratory (UoA-CNL) and the Networks Operations and Management Center. His research interests are in the design and performance analysis of broadband networks, and wireless/mobile communication systems and services. He has authored more than 150 papers in the above areas. Since 1995, he is leading the research activities of UoA-CNL in the area of mobile communications, in the framework of the Advanced Communication Technologies & Services (ACTS) and Information Society Technologies (IST) programmes funded by the European Union (projects RAINBOW, Magic WAND, WINE, MOBIVAS, POLOS, ANWIRE). He is chairman of the board of the Greek Universities Network, the Greek Schools Network, and member of the board of the Greek Research Network. In 1994, he received the Guanella Award for the Best Paper presented at the International Zurich Seminar on Mobile Communications.