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High performance wireless Ethernet 总被引:6,自引:0,他引:6
Heegard C. Coffey J.T. Gummadi S. Murphy P.A. Provencio R. Rossin E.J. Schrum S. Shoemake M.B. 《Communications Magazine, IEEE》2001,39(11):64-73
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结合FMC标准与IEEE 802.3ae协议标准,设计了一种基于FPGA夹层卡(FPGA Mezzanine Card,FMC)标准的万兆以太网卡,满足现代工业大数据量传输应用的要求。FMC标准接口可实现多通道高速接口,解决应用母板与网卡之间的数据传输瓶颈。使用Verilog硬件描述语言设计了地址解析协议(Address Resolution Protocol,ARP)与用户数据报协议(User Datagram Protocol,UDP)的硬件协议栈,实现开放式系统(Open System Interconnect,OSI)模型的传输层;Xilinx 10 G Ethernet subsystem IP与小型化可热插拔(Small Form-factor Pluggable,SFP)光接口实现OSI模型的网络层、数据链路层、物理层。通过FMC母板、万兆以太网卡、PC上位机组建的网络成功测试了万兆以太网通信。 相似文献
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提出一种基于IEEE802.17标准和IEEE802.3标准的弹性以太环节点设计方案,以及主要模块详细的功能设计,并给出了弹性以太环节点验证系统的设计方案.该方案既有效利用了RPR的特点,又实现了在城域网络中传输以太网数据和有效降低城域网络建设成本的目的. 相似文献
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为了提高通信系统的数据吞吐量,增加系统集成度,在IEEE 802.3ae标准的基础上,对万兆以太网技术进行了研究并实现。万兆以太网技术是基于FPGA实现的,FPGA完成的主要工作包括:完成与上层软件的指令和数据交互、数据的组帧/解帧、与物理层的接口管理等。物理层发送端主要完成数据对齐、变速并加扰、并串转换等工作,将串行数据发送给光电转换模块,接收端正好相反。经过万兆以太网标准仪器测试,传输速率达到了10 Gb/s,大大提高了系统间数据传输的速度和效率,简化了系统结构。 相似文献
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系统地介绍了以太网的基本概念,介质接入控制和物理层标准规范。以太网信号的帧结构、网络硬件设备、网络组成及主要性能,以及以太网信号在PDH、SDH/SONET中的传输等等。由于以太网中的各种设备必需通物理层接口器件才能与网络传输介质相连,因此本部分主要介绍物理层器件。 相似文献
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During the past decade, there has been much standardization effort for indoor or shot-range networks, as communication devices
and applications for such networks populate. As a prominent example of these activities, the IEEE 802.15.3 Task Group (TG)
published a standard for high-rate wireless personal area network (HR-WPAN). To support strictly timed multimedia services,
the TG adopts a time-slotted channel access protocol controlled by a central device (DEV). Although the channel time allocation
algorithm plays a key role in deciding the network performance, it remains unspecified in the standard. Therefore, in this
paper, we propose a novel feedback-assisted channel time allocation method for HR-WPAN. After initial channel times are allocated
based on packet inter-arrival time statistics, the allocation is dynamically adjusted by utilizing feedback information from
each DEV. The feedback information includes the buffer status, the packet transmission delay, and the physical transmission
rate. By utilizing this feedback information, the central DEV can allocate sufficient channel time for transmissions of pending
packets from a DEV. Moreover, the allocated channel times can be synchronized to the packet arrival times so that the overall
transmission delay is reduced. To cope with time-varying wireless channels, a dynamic rate selection algorithm assisted by
physical layer information is proposed in this paper. Performance evaluation is carried out through extensive simulations,
from which significant performance enhancements are observed. 相似文献
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SoftMAC: Layer 2.5 Collaborative MAC for Multimedia Support in Multihop Wireless Networks 总被引:1,自引:0,他引:1
Haitao Wu Yunxin Liu Qian Zhang Zhi-Li Zhang 《Mobile Computing, IEEE Transactions on》2007,6(1):12-25
In this paper, we present the challenges in supporting multimedia, in particular, VoIP services over multihop wireless networks using commercial IEEE 802.11 MAC DCF hardware, and propose a novel software solution, called Layer 2.5 SoftMAC. Our proposed SoftMAC resides between the IEEE 802.11 MAC layer and the IP layer to coordinate the real-time (RT) multimedia and best-effort (BE) data packet transmission among neighboring nodes in a multihop wireless network. To effectively ensure acceptable VoIP services, channel busy time and collision rate need to be well controlled below appropriate levels. Targeted at this, our SoftMAC architecture employs three key mechanisms: 1) distributed admission control for regulating the load of RT traffic, 2) rate control for minimizing the impact of BT traffic on RT one, and 3) nonpreemptive priority queuing for providing high priority service to VoIP traffic. To evaluate the efficacy of these mechanisms, extensive simulations are conducted using the network simulator NS2. We also implement our proposed SoftMAC as a Windows network driver interlace specification (NDIS) driver and build a multihop wireless network testbed with 32 wireless nodes equipped with IEEE 802.11 a/b/g combo cards. Our evaluation and testing results demonstrate the effectiveness of our proposed software solution. Our proposed collaborative SoftMAC framework can also provide good support for A/V streaming in home networks where the network consists of hybrid WLAN (wireless LAN) and Ethernet 相似文献
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以太网相关技术标准规范与标准组织简介(二) 总被引:1,自引:0,他引:1
中首先介绍电气与电子工程师学会(IEEE)组织概况,然后概括说明了IEEE关于局域网/城域网IEEE802.2标准系列、以太网集成电路标准图标,特别着重讨论了关于以太网的IEEE802.3系列标准、在SDH/WDM网络上传输以太网帧信号的相关规范和10吉比特以太网技术标准。最后指出,10吉比特以太网技术标准的开发和广泛应用将在通信领域展现出更加辉煌的明天。 相似文献
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以太网相关技术标准规范与标准组织简介(一) 总被引:2,自引:0,他引:2
中首先介绍电气与电子工程9币学会(IEEE)组织概况,然后概括说明了IEEE关于局域网/城域网IEEE802.2标准系列、以太网集成电路标准图标,特别着重讨论了关于以太网的IEEE802.3系列标准、在SDH/WDM网络上传输以太网帧信号的相关规范和lO吉比特以太网技术标准。最后指出,10吉比特以太网技术标准的开发和广泛应用将在通信领域展现出更加辉煌的明天。 相似文献
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A Cross-Layering Design for IPv6 Fast Handover Support in an IEEE 802.16e Wireless MAN 总被引:1,自引:0,他引:1
Broadband wireless access networks, such as the IEEE 802.16 standard for wireless metropolitan area networks (WMANs), aim to provide high bandwidth, low-cost, scalable solutions that extend multimedia services from backbone networks to wireless users. Because of a larger coverage area, portability and mobility have become significant issues for providing high quality mobile services, as it is crucial to minimize handover latency and maintain IP session continuity. As a result, such issues were addressed by the IEEE 802.16e task group on the mobile WMAN. However, the scope of the IEEE 802.16e standard did not include cross-layering approaches for the enhancement of upper layer handover performance. This article proposes a new cross-layering design for fast IPv6 handover support over IEEE 802.16e. First, we describe the IEEE 802.16 deployment architectures, as well as the link layer, handover procedures in IEEE 802.16e. Next, we describe the operation of fast IPv6 handover and point out the need for interaction between the network layer and the link layer for proper performance. Then, we propose a new cross-layering design to achieve a proper behavior of the fast IPv6 handover over IEEE 802.16e. Finally, we present handover scenarios for the proposed techniques and discuss the major factors that contribute to the handover latency. 相似文献
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The answers to many of the communications problems businesses face lie in the integration of telephony, data collaboration, and video communications with the desktop computer, doing it inexpensively, doing it seamlessly with the local area and wide area networks. The adoption of isochronous Ethernet (isoEthernet) by the IEEE 802.9 committee as the new multimedia standard in LANs has given rise to new technology that converges voice, collaborative video, and data at the desktop. The official name for isoEthernet is ISLAN16-T, and it is sponsored by the IEEE 802.9 committee. IEEE 802.9a, the document specifying the isoEthernet standard, became an official standard at the end of 1995. The intent behind the ISLAN16-T standard is to define a LAN transport capable of handling synchronous services such as voice and video while retaining compatibility with 10Base-T. ISLAN16-T opens the door to a multitude of new applications that can reshape work and communications habits to make businesses more productive, responsive, and profitable 相似文献
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The complementary characteristics of wireless local area networks (WLANs) and wideband code division multiple access (CDMA)
cellular networks make it attractive to integrate these two technologies. How to utilize the overall radio resources optimally
in this heterogeneous integrated environment is a challenging issue. This paper proposes an optimal joint session admission
control scheme for multimedia traffic that maximizes overall network revenue with quality of service (QoS) constraints over
both WLANs and CDMA cellular networks. WLANs operate under IEEE 802.11e medium access control (MAC) protocol, which supports
QoS for multimedia traffic. A cross-layer optimization approach is used in CDMA networks taking into account both physical
layer linear minimum mean square error (LMMSE) receivers and network layer QoS requirements. Numerical examples illustrate
that the network revenue earned in the proposed joint admission control scheme is significantly more than that when the individual
networks are optimized independently. 相似文献
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WLAN的出现,充分解决了有线网络先天性缺陷所带来的一系列问题。与有线网络相比,WLAN具备了很多特定优势。作为有线局域网的一种补充和扩展,WALN使计算机具有了可移动性,能快速、方便地解决有线网络不易实现的网络连通问题,成为今后网络发展的主导方向。IEEE802.11标准是IEEE制定的无线局域网标准,各厂商的产品在同一物理层上可以互相操作,这样就使得无线局域网的两种主要用途“多点接入”和“多网段互联”更易于低成本实现,从而为无线局域网的进一步普及打通了道路,文中介绍了几个常用标准的特点。 相似文献
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2002年6月12日,10Gbit/s以太网(10GbE)标准被IEEE正式通过.文章介绍了10GbE标准的体系结构,着重讨论了其物理层结构,最后给出了它的应用前景。 相似文献