IP over WDM光网络的演进趋势

由于IP业务的指数增长以及WDM在传送网中的主导地位,将IP业务直接承载于WDM系统的IP ver DM光网络成为理想的选择。IP over WDM光网络可分为三个阶段,即：点到点IPoverWDM、IP0ver可重构WDM、IPover光交换的WDM。     

基于GMPLS的IP over WDM

GMPLS(通用多协议标签交换)是MPLS技术向光网络发展的产物。它有效地实现了IP和WDM光网络的无缝结合,是IP over WDM发展的一种趋势。本文主要介绍了GMPLS通用标签的特点及实现形式,LSP(标签交换路径)技术,以及链路管理协议LMP的特点及实现方法。     

IP over WDM光网络的共享保护方式

共享保护方式是一种有效而又经济的保护方式。文章讨论了三种共享保护方式及各自的特点。使用交换光纤（OSF）的共享保护方式利用IP网络控制器来实现，主要应用于环形网络拓扑；利用OXC的共享保护方式基于多协议标记交换（MPLS）控制平面，可以用于任何网络拓扑结构；通过合理的逻辑拓扑而实现的共享保护则用于保护SONET/WDM和IP/WDM网络的设计。     

基于GMPLS的IP over WDM

GMPLS（通用多协议标记交换）是MPLS技术向光网络发展的产物。它有铲地实现了IP和WDM光网络的无缝结合，是IP over WDM发展的一种趋势。本文主要介绍了GMPLS通用标记的特点及实现形式，LSP（标记交换路径）技术，以及链路管理协议LMP的特点及实现方法。     

IP over WDM光网分层体系结构

介绍了传统的 IP over WDM光网实现方案 ,指出各种方案的优缺点。阐述了 IP directly overWDM光网的分层结构实现方案 ,分析了各层功能 ,详细讨论了光层和光适配层。在指出分层结构实现方案的利弊后 ,讨论了波长标记和多协议波长交换方案。     

多域光网络联合路由保护算法

研究了多域光网络中的路由保护问题。为了避免多域光网络通路保护二步算法可能导致的多域陷阱问题,提出了一种基于Suurballe算法扩展的多域联合路由保护算法。仿真表明,相比传统的多域通路保护二步算法,该算法资源利用率高,阻塞率低,平均每连接跨域数小。     

IP over DWDM光区域接入网络

本文介绍了基于IPover DWDM的光区域接入网络、IP路由器及波长路帱/转发器的概念，重点讨论了光区域接入网络的物理构成结构、接入节点的功能结构和网络连接等。指出这种结构是新电信运营公司的发展方向。     

光网络的保护策略

对光网络中的保护方法进行分类描述,结合当前的研究状况,对光网络保护算法的研究方向,提出相关见解.     

IP over GFP over WDM的适配研究

GFP是IP与光网络融合的一项关键技术。在介绍GFP的基础上,分析几种IP/GFP/WDM适配方案;在遵循ITU-TG.7041标准的基础上,对GFP进行了完善和创新,并通过实验验证了其可行性。     

IP voer WDM光网络及其生存性问题讨论

本文介绍了IP voer WDM光网络的演进过程与发展趋势；讨论了其生存性问题，包括光层生存性有关概念、分类及各自的优缺点，IP/MPLS层与WDM层联合生存机制的必要性以及这种联合机制需要解决的竞争问题=带宽资源共享问题和失效扩散问题等。     

IP over WDM网中的综合选路算法

研究了IP over WDM网中,当节点不具备波长变换能力并且配备有限光收发器对时,如何利用综合选路(IR)算法为到达业务请求建立标签交换路径(LSP)。提出一种新颖的辅助图模型(AGM)表示网络的当前状态,基于AGM提出一种动态IR算法-最小光收发器对法(MTA)。MTA总是选择占用光收发器对最少的通路来建立LSP,仿真结果表明：与已有算法相比,MTA可以降低全网的阻塞率,从而提高业务通过率,并且有利于减少业务连接所经光／电变换的次数。     

一种面向IP/GMPLS over WDM网络的优化综合路由算法

为了优化利用IP层和WDM层网络资源,在WDM网络集成辅助图模型的基础上,提出了一种面向IP/GMPLS over WDM网络的基于代价的优化综合路由算法,即CIR(Cost-basedIntegrated Routing).该算法将IP层和WDM层资源可用信息以代价函数形式给出,并将因网络拓扑结构和网络负载分布不均衡等产生的瓶颈链路以及带宽碎片问题也统一纳入考虑,由此将LSP建立问题转化为在集成辅助图上找出一条源、目的节点之间的最短通路问题.仿真结果表明:CIR算法有效地实现了IP和WDM两层资源的联合优化,提高了网络资源利用,降低了网络阻塞率.     

智能光网中的联合路由

在IP/MPLS智能光网络中的LSP路由分为独立路由和联合路由两类。由于综合考虑了光层和IP层的可用资源信息和拓扑信息,联合路由能够提供比独立路由方案更高的资源利用率。文中提出了联合路由算法的设计目标,综述了联合路由算法的研究现状,并给出了下一步的研究方向。     

波分复用网络的保护方式

首先介绍了在WDM网络中常用的光通道保护、光复用段保护方式及其实际使用方案,然后对WDM网络中采用不同保护方式的优缺点进行了分析,并对WDM网络中保护方案的设计提出了建议.     

基于GMPLS的IP over WDM

GMPLS(通用多协议标记交换)是MPLS技术向光网络发展的产物。它有效地实现了IP和WDM光网络的无缝结合,是IPoverWDM发展的一种趋势。本文主要介绍了GMPLS通用标记的特点及实现形式,LSP(标记交换路径)技术,以及链路管理协议LMP的特点及实现方法。     

High-Performance Hybrid-Switching Optical Router for IP over WDM Integration

Because pure electrical routers with their bandwidth limitations can hardly keep up with the tremendous traffic growth in the Internet, optical routers based on various optical switching techniques including optical wavelength switching (OWS), optical burst switching (OBS), and optical packet switching (OPS) have been suggested to cope with this problem. However, because OBS and OPS are both in their early experimental phase and OWS only provides coarse granularity switching, a hybrid-switching optical router with combined OWS and electrical packet switching is a necessity in order to accommodate the entire multi-granularity traffic with multi-service requirements in a cost-effective manner. Its coordination capability of optical circuit switching and electrical packet switching enables efficient/intelligent usage of network resources. In this paper, we first review research and developments of such IP routers employing optical switching/interconnection techniques and examine how these techniques can be used inside routers to scale node capacity and to improve optical Internet performance. We also present and study the performance of a terabit optical router with an optical-electrical hybrid-switching fabric. The node architecture is based on the idea of IP over WDM integration with Generalized Multi-Protocol Label Switching (GMPLS). The network-level performance evaluations show that the proposed hybrid-switching optical router is a cost-effective solution for building the next generation GMPLS-based multi-granularity optical Internet.     

A Bandwidth Guaranteed Integrated Routing Algorithm in IP over WDM Optical Networks

In this paper, we have developed an integrated online algorithm for dynamic routing of bandwidth guaranteed label switched paths (LSPs) in IP-over-WDM optical networks. Traditionally, routing at an upper layer (e.g., IP layer) is independent of wavelength routing at the optical layer. Wavelength routing at the optical layer sets up a quasi-static logical topology which is then used at the IP layer for IP routing. The coarse-grain wavelength channels and the pre-determined virtual topologies with respect to some a priori assumed traffic distribution are barriers to efficient resource use and inflexible to changing traffic. We take into account the combined knowledge of resource and topology information at both IP and optical layers. With this added knowledge, an integrated routing approach may extract better network efficiencies, be more robust to changing traffic patterns at the IP layer than schemes that either use dynamic routing information at the IP layer or use a static wavelength topology only. LSP set-up requests are represented in terms of a pair of ingress and egress routers as well as its bandwidth requirement, and arrive one-by-one. There is no a priori knowledge regarding the arrivals and characteristics of future LSP set-up requests. Our proposed algorithm considers not only the importance of critical links, but also their relative importance to routing potential future LSP set-up requests by characterizing their normalized bandwidth contribution to routing future LSP requests with bandwidth requirements. Moreover, link residual bandwidth information that captures the link's capability of routing future LSPs is also incorporated into route calculation. Extensive simulation was conducted to study the performance of our proposed algorithm and to compare it with some existing ones, such as the integrated minimum hop routing algorithm and the maximum open capacity routing algorithm. Simulation results show that our proposed algorithm performs better than both routing algorithms in terms of the number of LSP set-up requests rejected and the total available bandwidth between router pairs.     

IP over WDM联合路由框架

研究了IPoverWDMdirectly所面临的三大基本问题 ,重点对IP和WDM的联合路由框架进行了研究 ,分析了三种模型以及其中所用到的协议以及协议扩展。并对联合路由的控制面问题进行了研究 ,着重分析了对MPLS TE进行适当的光扩展以实现统一的控制平面。     

IP与传输网络结合的集成模型

随着IP／MPLS技术的发展，网络控制协议功能不断强大；随着自动光网络技术的发展，传统的传送网中已经引入动态交换的概念。在这些基础上，IP与传输网络的更紧密结合成为可能。本论述了IP与传输网络结合的集成模型，并对基于GMPLS的集成模型的实现作了详细分析。