基于PCE的WSON光网络RWA分配策略与仿真

为了有效分配WSON光网络中的波长资源,提出了一种基于路径计算单元(Path Computation Element,PCE)的波长交换光网络(Wavelength-Switched Optical Network,WSON)路由与波长分配策略.该策略通过PCE建立波长资源冲突避免表,并由目的节点与PCE进行通信确认,避免资源竞争问题的发生.将该策略下的网络阻塞情况与FF算法、RF算法进行对比仿真,仿真结果表明运用该策略可以有效抑制波长预留冲突,大大降低网络阻塞率.     

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。     

智能光网络标准化介绍

介绍了ITU-T,IETF和OIF等标准化组织在智能光网络标准化方面的最新进展,并介绍了华 为公司在智能光网络方面的工作进展情况。     

ASON路由协议OSPF—TE的分析与仿真

自动交换光网络（ASON）通过在传统光传送网络中引入路由协议、信令协议来实现网络的智能化。文章对ASON路由协议——基于流量工程开放最短路径优先协议（OSPF—TE）的基本概念和工作机制进行了分析研究，并仿真了OSPF-TE的一些网络性能，并得到一些有益的仿真结果。     

智能光网络控制平面模型的研究

首先介绍了IETF的基于GMPLS对等模型和ITU—T的ASON重叠模型，并且比较了它们之间的关系；接着阐述了基于GMPLS智能光网络控制平面的功能模块；最后在Berkeley实验室开发的NS-2网络仿真器平台上对基于GMPLS智能光网络模型进行了设计和仿真。     

一种改进的基于GMPLS多粒度光网络恢复机制

多粒度光网络(MGON)的生存性问题中增加了波带失效的故障类型,需要考虑和制定基于波带通道进行故障恢复的生存性策略.针对MGON中的节点失效提出了一种改进的基于GMPLS的共享备份恢复策略(GSR),采用故障链路源节点进行差异化恢复和共享备份恢复策略,可以减少因预留资源导致的成本.     

基于ASON全光通信方案实现

针对目前ASON网络的智能优势和电控不足,给出了智能化全光网络设计方案。介绍了基于ASON的全光通信技术要求,并给出了实现全光交换的节点部件即智能化OXC的结构。对方案中采用的协议、接口、组网方式以及通信实现过程进行了描述,最后对方案的优势进行了分析。     

基于GMPLS的智能光网络体系结构及其关键技术

介绍了基于GMPLS对等模型的智能光网络，阐述了GMPLS的协议栈结构和对MPLS的扩展，分析了GMPLS体系结构中的关键技术。     

GMPLS与自动交换光网络

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光网络的无缝融合，很好的满足了自动交换光网络控制面的需要。本文主要研究了GMPLS的接口类型和标签、自动交换光网络(ASON)的控制面以及GMPLS在ASON中的应用。     

波长交换光网络技术标准化现状及网络应用

波长交换光网络（WSON）将控制平面引入波长网络,实现波长路由的动态调度,提高网络调度的灵活性和网络管理的效率。主要对WSON技术的标准化现状和设备实现情况进行介绍,并给出WSON在实际网络中的应用部署建议。     

下一代光交换网络的智能控制平面技术

For the next generation optical switching networks, the intelligent control plane is a key enabling technique. In this paper, we review our recent research activities related to Generalized Multi-Protocol Label Switching ( GMPLS ) and OpenFlow-based control planes for both Wavelength Switched Optical Networks (WSON) and Elastic Optical Networks (EON).     

GMPLS协议中的路由和波长分配技术

因特网工程工作组（IETF）制定的通用多协议标签交换协议（GMPLS）,作为光网络的控制平面协议,推动了光网络的智能化进程。路由和波长分配问题（RWA）是光网络智能化的核心问题之一。在介绍RWA算法和GMPLS协议的基础上,分析了不同RWA算法、不同RWA机制对网络信息的需求,描述了GMPLS协议为解决RWA问题所做的标准化工作,并分析了与RWA相关的网络信息分发格式。     

下一代光网络中光路的快速建立

文章针对下一代光网络中光路快速建立的问题,介绍了IP-over-optical的网络体系结构,并在此基础上介绍了动态RWA问题和综合解决RWA问题的动态和半动态寻路算法,讨论了这两种算法的容错性能。     

一种新型的基于PCE的多层多域GM-PLS／ASON光网络体系结构

With the development of large-scale, multi-region and multi-layer networks, policy-based and constraint-based path computation is more and more complicated and dynamic routing becomes one of the key issues in GMPLS/ASON networks. To combine the advantages of both GMPLS control plane and PCE, novel dual routing engine architecture of multi-layer and multi-region scalable optical networks is proposed in this paper. The collaboration of group engine and unit engine makes it effective to optimize path computation especially under the condition of complex multi-constraints. The functional architecture of dual routing engine is detailed. Different potential co, operation relationships between group engine and unit engine are investigated and simulation results for multi-region and multi-layer routing schemes are analyzed.     

Multiple-Constraint-Aware RWA Algorithms Based on a Comprehensive Evaluation Model： Use in Wavelength-Switched Optical Networks

Because of explosive growth in Internet traffic and high complexity of heterogeneous networks,improving the routing and wavelength assignment (RWA) algorithm in underlying optical networks has become very important.Where there are multiple links between different the node pairs,a traditional wavelength-assignment algorithm may be invalid for a wavelength-switched optical networks (WSON) that has directional blocking constraints.Also,impairments in network nodes and subsequent degradation of optical signals may cause modulation failure in the optical network.In this paper,we propose an RWA algorithm based on a novel evaluation model for a WSON that has multiple constraints.The algorithm includes comprehensive evaluation model (CEM) and directional blocking constraint RWA based on CEM (DB-RWA).Diverse constraints are abstracted into various constraint conditions in order to better assign routing and wavelength.We propose using the novel CEM to optimize routing according to an assessed value of constraints on transmission performance.This eliminates the effects of physical transmission impairments in a WSON.DB-RWA based on CEM abstracts directional blocking conditions in multiple links between network nodes into directional blocking constraints.It also satisfies rigorous network specifications and provides flexibility,scalability,and first-fit rate for the backbone,especially in multiple links between WSON nodes.     

扩展资源预留协议的波长选择设计方案分析

主要研究基于路径计算单元( PCE)的波长交换光网络(WSON)中的波长分配问题.提出了PAWA(PCF Assistant Wavelength Assignment)方案,在可能发生冲突的path请求上做标记,来帮助目的节点选择波长,从而避免资源冲突.最后利用离散事件模拟工具OMNeT++进行了仿真分析,相比首次命中(FF)和随机命中(RF),PAWA方案扩展了信令,降低了阻塞率,并没有增加建路延时和资源利用率.     

An experimental switching-aware GMPLS-based lightpath provisioning protocol in wavelength-routed networks

In wavelength-routed optical networks, the high-delay introduced by the optical switching fabric for resource reservation increases critically the lightpath setup delay. In order to minimize the setup delay, Generalized Multi-protocol Label Switching (GMPLS) introduced the concept of Suggested Label Object (SL), which allows to start reserving and configuring the hardware with a proposed wavelength from the source node to the destination node. This solution is not optimal in wavelength selective networks (WSN) (i.e., without wavelengths converters). The need of guaranteeing the wavelength continuity constraint for end-to-end optical connections, combined with the lack of global wavelength-based link information (the source node is not aware of which wavelengths are available on each link), makes that the likelihood of establishing a lightpath using the proposed suggested label may be minimum. In this article, we propose an enhancement to the current GMPLS RSVP-TE signaling protocol with offset time-based provisioning that minimizes the lightpath setup, improving the overall network performance in terms of blocking probability and setup delay. Experimental performance evaluation has been carried out in ADRENALINE testbed, a GMPLS-based intelligent all-optical transport network.     

裸板测试与PCBA性能测试及使用功能分析探究

裸板测试-bare board test,又称"通断测试"。此检测工序是在整个电路板制程后质量检验中尤为重要关键的一个生产环节,因为它是保证客户原始设计网络关系、基本性能使用的电检测试工序。然而"通断测试"使用电检测试设备进行手动或自动测试过程中,由于在测试中测试治具与PCB形成接触,又因各种治具制作和PCB制成的因素导致最终成品板焊接盘形成接触式损伤,存在客户使用功能的性能隐患,所以为了达到客户焊盘的使用要求,在"通断测试"中采用一些特殊的测试设备、工具或物料进行测试、以此最大程度减少甚至杜绝焊盘接触式损伤,并对产品设计和通断测试这些可能产生隐患的方面进行有效的审核识别和生产控制,才可以使得成品板焊盘质量得到有效的保证。