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。     

智能光网络的路由架构及实现方案

本文对智能光网络路由架构中的路由控制器、链路资源管理器、协议控制器和路由信息数据库的功能进行了介绍 ,对分发路由信息过程中所使用的路由属性及路由消息作了描述 ,最后给出了基于 GMPL S的智能光网络控制平面的实现方案     

智能光网络的路由架构及实现方案

本文对智能光网络路由架构中的路由控制器、链路资源管理器、协议控制器和路由信息数据库的功能进行了介绍，对分发路由信息过程中所使用的路由属性及路由消息作了描述，最后给出了基于GMPLS的智能光网络控制平面的实现方案。     

智能光网络的路由技术

本文比较了传统IP网络和智能光网络路由技术的差别,介绍了满足QoS需求的智能光网络路由技术和适应智能光网络需要的路径选择算法的基本概念,设计基础,着重描述了在基于GMPLS扩展条件下约束最短路径算法的设计思路.     

智能光网备份路径恢复问题研究

提出了智能光网中的备份路径的本地恢复、全局恢复和更为合理的两阶段恢复方案,并在GMPLs控制平面内设计了若干信令协议用于实现备份路径的建立与故障通知和恢复过程。该方案充分考虑了备份路径保护,能够提高预建立备份路径保护方案的可靠性。     

分层路由——新一代智能光网络的路由技术

近几年数据业务正在持续快速地增长，为了满足日益增长的带宽需要和不断提高的服务质量要求，光网络正朝着智能化的方向不断发展。智能光网络，特别是自动交换光网络(ASON)的提出代表了光网络的发展方向，成为下—代光网络结构的研究焦点。为了提高网络的可扩展性和灵活性，满足ASON面向连接的网络特性，ASON网络采用了分层路由技术，通过拓扑抽象将ASON网络的路由结构层次化，利用聚合的路由信息简化选路过程。分层的路由结构使得运营商能够屏蔽网络的内部细节，提高网络的安全性，并且可以任意配置网络内部结构，使整个光网络具有高度的灵活性和可扩展性。本文深入分析了ASON网络的分层路由体系结构和分层路由对域间接口的功能要求，详细地介绍了适用于ASON分层路由的DDRP路由协议，并讨论了基于DDRP的ASON分层路由的组网实现方案。     

VPN在智能光网络中的应用

随着企业对VPN需求的不断增加，在智能光网络上构建OVPN将成为VPN技术一个新的发展方向。在数据网VPN的基础上引入OVPN的概念，介绍了实现OVPN的两种途径：基于硬件的OVPN和基于ASON的OVPN。重点阐述了在以GMPLS为基础的ASON网络中构建OVPN的参考模型、实现方法、特点等，指出OVPN作为智能光网络的一项重要新业务，必将对光网络从承裁网转变成可运营网络发挥重大作用。     

智能光网络的路由技术

路由技术是智能光网络的核心技术之一,如何把IP路由技术运用到智能光网络中,以及如何利用路由技术提高智能光网络的生存性已成为研究热点.文中综述了光网络中路由技术的特点,分析了当今国内外智能光网络的部分路由算法,深入研究对比了它们各自的优缺点,以及对智能光网络生存性产生的影响,预测了智能光网络路由技术的未来发展趋势.     

智能光网络中的路由和波长分配问题

随着下一代智能光网络概念的提出，应用于传统光网络的路由和波长分配方法面临着许多新的挑战。本以自动交换光网络为代表，分析了智能光网络中不同类型连接的特点和实现路由和波长分配的控制软件模块，并着重从路由模式、多粒度分层选路、路由和波长分配算法、信令路由协议等几个方面出发，对智能光网络中的路由和波长分配问题进行了深入的探讨。同时提出了相应的解决方案。     

超宽技术、智能光网在智能家庭中的应用

目前接入网技术正向着管道超宽化、运维智能化的方向发展,如何将高速带宽连接延伸到终端用户,如何用全新的多样的业务来填充大带宽,是提高用户体验的关键.以大带宽为基础,以家庭娱乐为突破口,依托视频业务终端为入口,实现内容以及应用增值将是大势所趋.通过云管端的深度融合,打造合作共赢的智慧家庭生态圈,为用户提供丰富优质的业务体验,将是智慧家庭发展的方向.     

IP over WDM光网络联合保护策略

随着Internet和网络技术的发展,IP over WDM光网络成为下一代通信网最理想的解决方案。因此,IP over WDM光网络的生存性是下一代通信网成功与否的关键。在传统的保护策略中,IP层和WDM层之间不交换网络的状态信息。探讨了IP层和WDM层保护机制互相协作的必要性,并在通用多协议标签交换GMPLS的基础上,提出了联合保护策略的思想。     

基于业务的智能光网络生存性研究

目前对于智能光网络（ION）生存性方面的研究主要是针对光网络本身，基于静态的资源配置和管理机制对于快速变化的业务需求而言缺乏灵活性，难以满足未来智能光网络中复杂业务的需求。基于业务的智能光网络生存性策略，可以解决现有网络生存性策略与业务侧的生存性需求之间的差异。通过将对生存性需求的描述和定义从网络侧转移到业务侧，以业务对生存性的需求为核心，能很好地实现智能光网络中对生存性策略的控制和实现。     

卫星综合信息网的架构设计及路由算法

卫星综合信息网是未来空间信息技术发展的方向之一。本文针对卫星综合信息网应用设计了一种由静止轨道、中轨道和低轨道卫星节点构成的结构简洁的三层卫星网络架构,每一层网络仅使用永久性链路形成稳定拓扑,不同层网络在分簇的基础上使用可视时间较长的星间链路建立跨层连接。本文进一步设计了在该架构下的最小延迟路由算法。OPNET上的仿真实验表明,本文所设计的卫星综合信息网架构稳定,具有较强的通信承载和适应节点故障的性能。     

光网络中的路由信息交换

分析了IP路由路和核心光网络之间 ,光子网内部以及光子网之间的路由信息交换。这种路由信息交换在自动建立穿越多个光子网的端到端光通道的过程中是非常重要的。UNI路由信息交换 ,分为三种类型 ,并对部分对等模型和完全对等模型做了详细分析 ,此外 ,对NNI路由信息交换以及端到端的光通道动态供给模型也做了粗略分析。     

Invited: Routing Strategies for Capacity-Efficient and Fast-Restorable Mesh Optical Networks

Wavelength division multiplexed (WDM)-based mesh network infrastructures that route optical connections using intelligent optical cross-connects (OXCs) are emerging as the technology of choice to implement the next generation core optical networks. In these architectures a single OXC is capable of switching tens of terabits of traffic per second. With such data transfer rates at stake, it becomes increasingly challenging for carriers to (1) efficiently and cost-effectively operate and manage their infrastructure, and (2) cope with network failures while guaranteeing prescribed service level agreements (SLAs) to their customers. Proper routing of primary and backup paths is a critical component of the routing and restoration architecture required to meeting these challenges. In this paper we review some of the various strategies and approaches proposed so far to intelligently route connections while at the same time providing guaranteed protection against various types of network failures. We explore the tradeoffs associated with these approaches, and investigate in particular different, sometimes competing aspects, such as cost/capacity required, level of protection (link vs. node failure), restoration time, and complexity of route computation.     

集成化的光因特网技术

未来的光网络在体系结构复杂程度方面必须降低,以便节省费用和便于管理。将IP构建于光层上无疑是正确的解决办法。通用多协议标记交换(GMPLS)技术的出现,为光因特网的实现提供了一种新的方式。分析了IP层与WDM层的组网模型,基于GMPLS技术,建立了新的集成化的光因特网网络体系结构,分析和讨论了基于GMPLS的光因特网的控制平面的特征。研究结果为实现光因特网提供了一种新方法。     

神经网络最短路径路由算法

最短路径路由算法一直是分组交换网络的研究热点。飞速发展的计算机网络对路由算法的反应速度提出了更高的要求。神经网络作为一种新的组合优化计算工具,以其固有的并行执行方式以及潜在的硬件实施能力,使其在网络路由方面的应用得到较大关注。对神经网络最短路径路由算法的模型、发展做了较为细致的阐述,并指出了存在的不足和将来的研究方向。     

The Role of Network Topologies in the Optical Core of IP-over-WDM Networks with Static Wavelength Routing

In this paper, we present a performance analysis of network topologies for the optical core of IP-over-WDM networks with static wavelength routing. The performance analysis is focused on regular degree four topologies, and, for comparison purposes, degree three topologies are also considered. It is shown that the increase of the nodal degree from three (degree three topology with smallest diameter) to four (degree four topology with smallest diameter) improves the network performance if a larger number of wavelengths per link is available. However, the influence of wavelength interchange on the nodal degree gain is small. The performance of regular degree four topologies with smallest diameter is also compared with the performance of mesh–torus topologies (which are also degree four topologies), and it is shown that the blocking probability of degree four topologies with smallest diameter is about two orders of magnitude lower than the blocking probability of mesh–torus topologies. It is also presented a performance comparison of WDM-based networks with nodal degrees ranging from two to five and it is shown that the increase of the nodal degree from two to three leads to high nodal degree gains, while de increase of the nodal degree from four to five leads to low nodal degree gains. These results show that degree three and degree four topologies are very attractive for use in the optical core of IP-over-WDM networks.     

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.