两纤WDM全光环网的保护和恢复与波长分配

研究了WDM环网的保护和恢复与波长分配问题，提出了一种改进的Greedy波长分配算法，仿真计算结果表明，该算法应用于WDM共享保护环(SPRING)获得了较高的波长利用率，同时本文比较了WDM环网的不同保护和恢复结构对波长资源配置的要求。     

城市光传送网WDM环网技术要求

介绍了WDM环网的主要技术,以及WDM环网在城市应用时应考虑的一些因素。 宽带城市网;;城市光传送网;;WDM环网;;波长转换器保护倒换子速率复用     

城域WDM环网及其应用

文章阐述了城域WDM环网的节点结构、保护方式、波长转换器、子速率复用和光网络管理等,给出了WDM环网在城域应用时应考虑的一些因素,并分析了运营商所关心的系统成本问题。     

城域WDM环网及其应用

文章阐述了城域WDM环网的节点结构，保护方式，波长转换器，子速率复用和光网络管理等，给出了WDM环网在城域应用时应考虑的一些因素，并分析了运营商所关心的系统成本问题。     

WDM光环网的几种保护倒换方案

WDM光网络技术的应用正迅速地提升传输速率与带宽,不断地促进着电信业的发展。WDM光网络的可靠性与生存性变得日益重要。目前的研究热点是在网络的生存性和可重构性方面开发类似于SONET/SDH环网保护的WDM光环网结构,使之具备在经受各种网络故障后能够维持可接受的业务质量的能力。与SDH光环网相比,WDM光环网具有自身的特点：光层的保护与恢复时间比SDH电层快,光层恢复可靠性高,光层恢复成本低,光层保护支持多协议、多业务恢复等等。WDM光网络在传统的传送网络的电通道层和物理层之间引入光层。光层由光通道层、光复用段层…     

近阶段WDM网络技术的发展与应用

首先简要介绍了WDM技术,之后讨论了WDM环网和智能光网络,最后介绍了WDM技术在国内外的发展情况。     

城域WDM光传送网——2纤OADM环网技术概要

本阐述了一种城域WDM传送网-2纤OADM环网的主要技术，如OADM环网节点的3种基本结构、环网的保护方式、波长转换器、子速率复用和城域光网络管理等，给出了OADM环网在城域应用时应考虑的一些因素，并分析了运营商所关心的系统成本问题。     

基于分类可靠性的WDM环网设计

利用分类可靠性概念解决WDM多纤双向环网中的路由和波长分配问题。基于分类可靠性概念和环网的重用保护波长机制,提出了一种改进的最难重用优先算法。利用该算法,可以在满足每个连接可靠性要求的同时,使整个环网所需的波长里程数最小。     

WDM网状网中的基于平面构造的业务量疏导算法

将多个低于一个波长带宽的低速业务流复用到一个波长上传输的业务量疏导已经得到越来越多 的研究。WDM/SDH环网中的业务量疏导已得到大量研究,WDM网状网中的业务流疏导问题研究相对较少。该文研究静态环境下波长数目受限的业务量疏导问题,提出了一种基于平面构造的启发式业务量疏导算法。仿真结果表明该算法比已知的算法具有更好的性能。     

波分复用环网中带内串扰的精确分析

分析了波分复用 (WDM)全光通信环网中的串扰起因 ,指出单纤 WDM环网中的串扰分析可以简化为单一串扰源的情况。接着从接收机检测光电流的概率分布函数出发 ,给出了单一串扰源的精确误码率表达式 ,串扰功率代价的分析结果与实验测量非常吻合。     

波分复用光网络的自愈方法分析

WDM (WavelengthDivisionMultiplexing ,波分复用 )系统的应用使得大容量的业务日益集中于同一系统内 ,这同时提高了对网络自愈性能的要求 ,从而导致各种自愈技术的发展。因为光器件具有高速交换的优点 ,因而从光层对业务恢复具有极大的优越性。文中主要分析了几种典型的光层的自愈方法     

Metro WDM networks: performance comparison of slotted ring and AWG star networks

Both wavelength-division-multiplexing (WDM) networks with a ring architecture and WDM networks with a star architecture have been extensively studied as solutions to the ever increasing amount of traffic in the metropolitan area. Studies typically focus on either the ring or the star and significant advances have been made in the protocol design and performance optimization for the WDM ring and the WDM star, respectively. However, very little is known about the relative performance comparisons of ring and star networks. In this paper, we conduct a comprehensive comparison of a state-of-the-art WDM ring network with a state-of-the-art WDM star network. In particular, we compare time-slotted WDM ring networks (both single-fiber and dual-fiber) with tunable-transmitter and fixed-receiver (TT-FR) nodes and an arrayed-waveguide grating-based single-hop star network with tunable-transmitter and tunable-receiver (TT-TR) nodes. We evaluate mean aggregate throughput, relative packet loss, and mean delay by means of simulation for Bernoulli and self-similar traffic models for unicast traffic with uniform and hot-spot traffic matrices, as well as for multicast traffic. Our results quantify the fundamental performance characteristics of ring networks versus star networks and vice versa, as well as their respective performance limiting bottlenecks and, thus, provide guidance for directing future research efforts.     

一种新的集成自愈技术及其算法

本文首先提出了容量平衡优化（ＣＥＰ）、共享自愈环（ＳＳＲ）和分布式动态自愈网（ＤＳＨ）三者集成的自愈技术,提出了基于最短路由业务量阵（ＳＲＭＴ）的ＳＳＲ空闲容量分配算法,而对于ＤＳＨ,从端到端重选路由和网络资源利用率的观点看,基于通道恢复技术比基于链路恢复技术更有效,本文提出了基于通道恢复的集成自愈设计技术及其算法。数值结果表明：本文提出的集成自愈技术及其算法可有效地节约容量需求。     

传输规划SDH与WDM网络的经济性比较

分析了传输网络升级时引入点对点WDM系统,来承载SDH系统的合适时机;提出了SDH环和WDM环的成本构成模型,计算分析了在不同的环节点数量和不同的业务流量情况下二者的成本。通过SDH网络和WDM网络的经济性比较,指导网络规划建设SDH向WDM的发展演进。     

AWG-based metro WDM networking

A plethora of metropolitan area wavelength-division multiplexing networks have been proposed and examined in recent years with the aim to alleviate the bandwidth bottleneck between increasingly higher-speed local/access networks and high-speed backbone networks. Many of the considered metropolitan area networks use the arrayed waveguide grating as an optical building block. As we review in this article, in ring, interconnected ring, and meshed metro WDM networks, the AWG is typically used to realize wavelength multiplexers, demultiplexers, or optical add-drop multiplexers without capitalizing on spatial wavelength reuse. By using the AWG as a wavelength router, highly efficient star metro WDM networks can be realized due to extensive spatial wavelength reuse. We give an overview of star metro WDM networks that are able to meet modular upgradability, transparency, flexibility, efficiency, reliability, and protection requirements of future metro networks. AWG-based star networks also enable an evolution path of ring networks toward highly efficient and fault-tolerant hybrid star-ring metro network solutions.     

Metropolitan area packet-switched WDM networks: A survey on ring systems

We provide a comprehensive survey of packet-switched ring metro WDM networks. We first review current standardization and testbed activities, then we provide a categorization of ring WDM networks.We structure our survey according to a classification of the medium access control (MAC) protocols employed in the networks. Throughout the article we pay close attention to the key factors that govern the throughput-delay performance of the networks, such as the source vs. destination stripping of the data packets from the ring and the a priori or a posteriori access strategies. We also consider fairness aspects and QoS support in the networks.     

RINGOSTAR: an evolutionary AWG-based WDM upgrade of optical ring networks

The paper describes the study of the multichannel upgrade of IEEE Standard 802.17 Resilient Packet Ring (RPR) in particular and optical single-channel ring networks in general by making use of wavelength-division multiplexing (WDM). The paper describes and discusses a novel evolutionary multichannel upgrade approach that uses WDM on a central passive arrayed-waveguide grating (AWG)-based single-hop star network rather than on the ring. The AWG-based star subnetwork allows for a dramatically larger spatial reuse of WDM wavelength channels than conventional upgrades of optical single-channel ring networks that use WDM on the ring where all nodes need to be WDM upgraded. In the resultant hybrid optical ring-star network, termed RINGOSTAR, only a subset of the nodes are required to be WDM upgraded with a single additional tunable transceiver in order to improve the performance dramatically. The novel concept of proxy stripping is also introduced, which is used to route ring traffic on single-hop short cuts across the star subnetwork rather than the peripheral ring, resulting in a dramatically increased spatial reuse factor on the ring. By means of analysis, the performance of RINGOSTAR is investigated in terms of mean hop distance, spatial reuse, and capacity. The findings show that RINGOSTAR significantly outperforms unidirectional, bidirectional, and meshed WDM rings. Finally, the tradeoffs of RINGOSTAR are addressed.     

Multicast Capacity of Packet-Switched Ring WDM Networks

Packet-switched unidirectional and bidirectional ring wavelength division multiplexing (WDM) networks with destination stripping provide an increased capacity due to spatial wavelength reuse. Besides unicast traffic, future destination stripping ring WDM networks also need to support multicast traffic efficiently. This article examines the largest achievable transmitter throughput, receiver throughput, and multicast throughput of both unidirectional and bidirectional ring WDM networks with destination stripping. A probabilistic analysis evaluates both the nominal capacity, which is based on the mean hop distances traveled by the multicast packet copies, and the effective capacity, which is based on the ring segment with the highest utilization probability, for each of the three throughput metrics. The developed analytical methodology accommodates not only multicast traffic with arbitrary multicast fanout but also unicast and broadcast traffic. Numerical investigations compare the nominal transmission, receiver, and multicast capacities with the effective transmission, receiver, and multicast capacities and examine the impact of number of ring nodes and multicast fanout on the effective transmission, reception, and multicast capacity of both types of ring networks for different unicast, multicast, and broadcast traffic scenarios and different mixes of unicast and multicast traffic. The presented analytical methodology enables the evaluation and comparison of future multicast-capable medium access control (MAC) protocols for unidirectional and bidirectional ring WDM networks in terms of transmitter, receiver, and multicast throughput efficiency.     

Optical Network Survivability: Protection Techniques in the WDM Layer

This paper is an introduction to survivability of WDM networks. All the main optical protection techniques proposed as far as now for the WDM layer are classified and reviewed. In particular, commonly adopted protection strategies for ring and mesh networks are explained. Moreover, off-line planning of WDM networks able to support path protection is briefly introduced. Finally, an example of heuristic network-capacity optimization is presented, discussing results obtained by considering a case-study network.