一种Tb/s量级带宽的光电混合路由交换系统的结构

提出一种采用光互连网络作为大容量路由器中的信息传输载体,以VCSEI/PIN作为光电、电光转换收发接口,用高速IC芯片来处理信息的光电混合太比特量级的大容量路由交换系统方案.通过采用高速分组交换芯片、可扩展的交换结构与共享储存排队方法,实现了交换机构规模可扩展到1024×1024,端口速率为2.5 Gb/s,信元丢失率小于l0-9的新型的光电混合路由交换核心模块.     

基于阵列波导光栅的大规模光交换系统研究

光交换系统是波长路由、中心数据传输中的核心部分,目前光网络的发展方向是实现高速、多端口数和大容量光交换。采用 AWG(阵列波导光栅)的波长路由技术结合高速波长可调激光器,是实现大规模光交换系统中纳秒级开关时间的最有效的技术方案。文章分别从 AWGR(阵列波导光栅路由器)的周期性、串联、并联以及串并联等4个方面,对不同的架构方案进行了阐述。     

光突发交换网络技术研究

光纤传输技术和光网络技术的发展使得光网络成为现代高速宽带网络的基础骨干网。文章论述了三种光交换技术,并详细分析了光突发交换网络技术原理、交换结构及相关网络协议。在目前光器件和光信息处理方式未取得重大突破之时,光突发交换技术集成光电路交换和光分组交换的优势并且实现方式可行,能满足现有大容量、高速率的多媒体信息交换与传输,将成为下一代光IP骨干网的核心技术。     

光分组交换技术

光分组交换以其大容量、高速化、无电磁干扰等优良特性受到世界各国的重视。尽管目前对光交换的研究尚处于起始阶段，但随着宽带通信业务的发展和对光交换技术的深入研究，光交换技术将不断进步和完善。对光分组交换的特点及其与电分组交换的区别进行了讨论，并介绍了两处比较典型的光交换结构，最后对几种光分组编码方法进行了介绍和比较。     

未来光网络中的交换路由器

IP业务的爆炸式增长与DWDM技术的突飞猛进为新的WDM网络直接承载IP业务创造了条件。光交换和交换路由器的发展提供一种集成了智能IP路由技术和大容量光交换网络的交换路由器模型。这种交换路由器支持高QoS保证 ,简化了光核心网络结构 ,是近期光联网的理想解决方案     

基于光总线的无阻塞IP交换网络的工程实现

本文提出并实现了一种应用于路由器的基于光总线的无阻塞IP交换网络,该交换网络采用基于光的三平面负荷分担的总线结构,彻底克服了高速电背板工程实现的一系列难题。采用三平面负荷分担的全光总线交换网络结构,一方面有利于降低路由器成本,另一方面,也是出于系统冗余设计的考虑。该交换网络应用于国家“863”计划重大课题核心路由器－OmniRouter880的研制,样机验收测试结果表明基于光总线的无阻塞IP交换网络具有良好的性能,达到了课题指南的要求。     

SONET与WDM技术的比较

同步光网络(SONET )和波分复用( WDM )是目前组建高速光网络的主要技术,这两种技术充分利用光纤的低损耗带宽,实现超大容量的信息传输, 完成大容量信息交换。全面分析了 SONET 的性能、优缺点,以及 SONET 与 SONET 数据分组(PoS )之间的技术差别;介绍了 WDM 光交换系统的输入接口、交换结构、输出接口和控制单元 4 个组成部分及每部分的功能,重点研究 WDM 光网络的数据分组编码技术、争用解决方案和转向路由技术等关键技术。     

未来光网络中的交换路由器

IP业务的爆炸式增长与DWDM技术的突飞猛进为新的WDM网络直接承载IP业务创造了条件,光交换和交换路由器的发展提供一种集成了智能IP路由技术和大容量光交换网络的交换路由器模型。这种交换路由器支持高QoS保证,简化了光核心网络结构,是近期光联网的理想解决方案。     

核心路由器线路卡高速接口技术概述

太比特路由器由于具有庞大的交换容量,高速大容量高密度端口,分布式的路由和控制,其研制的复杂度高,需要解决许多关键技术问题。针对太比特路由器线路卡高速接口问题,本文综述了目前最新相关技术。     

带VOQ的输入队列交换网络中的分组调度算法研究

交换技术已经成为高速路由器的核心技术。本文基于目前高速交换技术所采用的主要体系结构,带有虚拟输出缓冲队列(VOQ)的输入队列交换结构,分析已经存在的各种调度算法的性能,并设计基于遗传算法的调度策略,提供IP数据网络的QoS对吞吐量和抖动的保障。     

光分组交换网络中光纤延迟线缓存技术

光分组交换网是全光网络发展的必然趋势.然而,光分组交换网络发展的瓶颈是光缓存技术.目前,在光域比较现实的还是采用光纤延迟线(FDL)作光缓存.重点研究了光纤延迟线光缓存技术,对FDL光缓存技术进行了深入的分析和归纳,并对每一种光纤延迟线光缓存调度策略的优缺点都进行了细致的分析.最后指出了光纤延迟线光缓存技术的未来研究重点和发展方向.     

核心通信网的光分组交换

文章首先简单说明了新一代通信网需要使用分级交换的由来。接着详细叙述了光分组交换在未来光通信网的应用，包括节点结构、分组格式、输入、输出接口和一些特别重要的技术，如再生、同步、信头处理、缓冲、空间交换和波长转换等。     

Ingénierie des systèmes de commutation optique et des réseaux locaux à large bande sur fibres optiques : analyses et perspectives

This paper first reviews how switching evolves in the ISDN environment with emphasize placed on changes in conventionnal time-division switches, then assesses techniques and technologies usable in optical switching and broadband networks : optical space-division switching systems (architecture, technologies based on dielectrics, semiconductors, photorepactive material) and optical time-division switching (optical memories based on delay lines and on bistable components multiplexing); multiple access networks (tdma, multiple access by code) ; switching using spread spectrum (bit switching); wavelength switching (multiplexer-demultiplexer, tunable laser and filters) ; packet switching in multi-wavelength networks (broadband networks standardization, local area networks with bus, passive star or multi-star configuration).     

A cellular neural network for packet selection in a fast packetswitching fabric with input buffers

We propose an implementation in terms of a cellular neural network (CNN) of the packet selection discipline in an input queueing fast packet switching (FPS) fabric. A neural network is designed which is devoid of spurious (suboptimal) responses and is guaranteed to take optimal decisions for switching packets. Such a neural network permits to lower the buffer memory requirements and to achieve throughput-mean switching delay performance close to the optimum (output) queueing alternative     

未来光因特网中的光交换方式及其发展趋势

Internet的业务流量正以每六个月翻一番的速度快速增长,未来网络中,数据业务超过话音业务只是时间问题,因此,基于电路交换的电信网升级到支持基于分组交换的数据业务是不可避免的,但是对因特网来说,由于光逻辑与光存储等器件不成熟,发展全光分组交换,技术上异常困难。另一方面,近来新提出的光突发交换,技术上相对简单,性能特点优异,因而成为更理想的选择,本文介绍了全光分组交换和光突发交换的研究现状,比较了两者的优缺点,最后指出改进光突发交换性能的两种方式。     

Performance Analysis of a Packet Switch Based on Single-Buffered Banyan Network

Banyan networks are being proposed for interconnecting memory and processor modules in multiprocessor systems as well as for packet switching in communication networks. This paper describes an analysis of the performance of a packet switch based on a single-buffered Banyan network. A model of a single-buffered Banyan network provides results on the throughput, delay, and internal blocking. Results of this model are combined with models of the buffer controller (finite and infinite buffers). It is shown that for balanced loads, the switching delay is low for loads below maximum throughput (about 45 percent per input link) and the blocking at the input buffer controller is low for reasonable buffer sizes.     

An optical router with multistage management functions for asynchronous optical packet switching network

An optical router with multistage distributed management features for the asynchronous optical packet switching (OPS) network is presented, which can improve switching capacity and all-optical scalability. A compact recycling-fiber-delay-line (Rec-FDL) based collision resolution mechanism is proposed to resolve the contentions for asynchronous and variable length optical packets. The analysis models of stabilities, packet loss rates (PLR) and average packet waiting latencies (PWL) for the router are developed based on the timer based optical packet assembly algorithm. The simulation shows that PLR and PWL for a 400-byte optical packet transmitted in the 32 wavelengths dense wavelength division multiplexing (DWDM) system equal to 3.48 × 10⁻⁴ and 0.072 ns, respectively. The non-blocking switching can be realized for the packets with lengths less than the buffer granularity of the Rec-FDL, and the optimized performance for the proposed router can be obtained through properly selecting of the system parameters.     

Performance of two-stage shared fiber delay line optical packet switch under bursty traffic

Packet contention is a major issue in an optical packet switching network. It is not a trivial task to resolve contention due to lack of optical RAM technology. This article proposes a two-stage shared fiber delay line (FDL) optical packet switch for contention resolution. In this article, shared FDLs are used to buffer optical packets, in which a pool of buffer memory is shared among all switch output ports. Most of the existing optical buffering schemes are output-based which require a huge number of FDLs as well as a larger switch size that incur extra implementation cost. However, a shared buffering approach is considered in this article in order to reduce implementation cost. In this article, FDLs are implemented in two stages using an extremely simple auxiliary switch. The proposed switch architecture leads to more efficient use of buffer space. The superiority of the proposed switch architecture has been established by means of extensive simulations. The performance of the proposed switch is investigated under bursty traffic. Simulation result shows that the proposed switch can achieve satisfactory performance at the price of a reasonable amount of FDLs. Moreover, the significance of the proposed switch is confirmed by simulation.     

Light-Frames-pragmatic framework for optical packet transport: extending ethernet LANs to optical networks

In this paper, a network architecture for the realization of a pragmatic framework for optical packet transport called the light-frame (LF) framework is proposed. The architecture enables the transport of packets over optical media. While doing so, it relaxes the need for address recognition as well as high-speed switching, which are the two key hindering factors that have prevented contemporary optical packet transport solutions from being deployed. Using this framework, a tradeoff was achieved between cost (maturity in deployment) and performance (network efficiency). The idea is to create a logical topology that enables N/sup 2/ connectivity, yielding sublambda granularity, and thereby facilitating packet transport. Methods for topology discovery and conflict resolution are proposed. This paper also discusses stochastic as well as optimization analysis of the framework. The fiber resource requirements of this network solution are compared to a leading access networking solution-passive optical networks (PONs)-and cost benefits are shown. The LF concept due to its finely granular application, despite a present technological bottleneck, presents a good implementation case that allows it to be pushed for next-generation optical packet transport, especially in the access area.     

A Modular, Scalable, Extensible, and Transparent Optical Packet Buffer

We introduce a novel optical packet switching buffer architecture that is composed of multiple building-block modules, allowing for a large degree of scalability. The buffer supports independent and simultaneous read and write processes without packet rejection or misordering and can be considered a fully functional packet buffer. It can easily be programmed to support two prioritization schemes: first-in first-out (FIFO) and last-in first-out (LIFO). Because the system leverages semiconductor optical amplifiers as switching elements, wideband packets can be routed transparently. The operation of the system is discussed with illustrative packet sequences, which are then verified on an actual implementation composed of conventional fiber-optic componentry