基于拓扑感知的可重构服务承载网动态重构算法

可重构信息通信基础网络通过构建服务承载网的方式为业务提供自适应的承载服务。针对高效利用有限底层资源的问题,提出一种基于资源关键度进行动态映射的服务承载网构建算法。算法将通过节点或链路的最短路径数作为资源关键度的衡量指标,区别对待底层资源;并实时动态感知关键资源的使用状况,依据不同业务需求对服务承载网进行自适应调整。仿真结果表明,算法在构建成功率、收益花费比和资源均衡度等方面均具有良好性能。     

MPLS-TP光网络中基于多维感知的信令机制

当前基于 MPLS-TP(多协议标签交换-传送架构)的光网络普遍存在网络动态变化并且不能充分感知上层业务的多样化需求的问题。针对这个问题，文章提出了一种基于多维感知的信令机制。该机制充分利用业务感知技术和网络感知技术，以期实现光网络对上层业务多样化的支持能力。仿真结果验证了该机制的有效性，证明该机制降低了业务连接建立时的冲突率和时延，提高了光网络的光路分配与业务需求之间的匹配效率。     

基于业务感知的下一代互联网QoS控制架构及关键技术

下一代互联网是业务驱动的融合网络,提供具有不同QoS需求的IP业务是其面临的关键问题之一.本文针对下一代互联网"业务丰富多变、网络加速融合"的特点,面向下一代互联网建设、融合和应用中面临的多业务承载、业务感知识别、服务质量区分保障和网络流量控制管理等问题,建立了业务智能感知模型,对各种新型业务流量的QoS控制架构及关键技术做了研究.     

光互联网中的业务感知和波长调度机制研究

提出了使用广义到达时间间隔的贝叶斯网络业务分类感知算法和基于业务感知的光互联网波长调度机制.仿真结果表明,使用广义到达时间间隔的贝叶斯网络业务感知算法获得的平均感知准确率可高达98%,同时训练数据中业务类型所占比例与该类型业务的感知准确率有密切关系.基于业务感知的波长调度机制在获得更高波长资源利用率的同时,能够实现光网络资源与业务需求的更好适配.     

无线通信中的绿色自组织技术

针对未来通信系统的节能问题,文章介绍了具有自管理、自配置、自优化以及自愈能力的绿色自组织网络及其相应的关键支撑技术,如融合网络架构下的业务预测与感知、新型无线网络架构下的智能资源分配、异构网络间的绿色协作和动态智能组网等。在此基础上文章提出了一种联合考虑能耗及负载均衡的动态扇区、小区关断方法,从而在保证用户服务质量的条件下有效降低网络的能量消耗。     

基于业务感知的下一代网络服务质量管理模型

下一代网络(NGN)是基于软交换、业务网与承载网分离的多业务融合网络。由于其多业务特性,出现了对业务流进行区分的业务感知技术,并将在NGN中起重要作用。NGN结构及特性的革命性变化,也对NGN的网管技术提出了新的要求,带来了新的挑战。NGN的多业务特性要求其网管技术能够实现对业务层面的管理和监测,从而为NGN提供高品质业务打下基础。文中提出了一种能动态业务感知的网管监测系统的智能代理结构模型。     

面向业务感知的共享链路保护策略研究

针对传统弹性光网络采用专用路径1+1保护策略存在资源浪费的问题,文章提出了一种共享链路保护策略.在检测到链路故障后,柔性光转发器切换至共享保护链路,并根据业务的优先级和请求频率重排业务权重,依据业务权重提供差异化的路由和频谱分配.此外,文章提出一种以物理网络拓扑结构、业务需求集合和优质业务量占比为约束条件,以最小化频谱...     

5G业务无线承载方案探讨

由于5G业务的多样性和网络的复杂性,传统的单独基于信道质量或基于负荷的无线承载策略并不能满足用户差异化的网络需求.因此5G网络需要智能无线承载策略,即以感知提升为目标,综合考虑业务需求、网络负荷、信道质量、终端能力等各种因素,将用户引导到最优目标频点,以实现网络资源与业务需求精确匹配,实现业务体验最优.     

分组域承载网4G回传承载优化

主要阐述4G分组域承载网网络架构,在视频业务、4G流量激增的业务驱动下,如何实现保障业务感知,做到网络架构最优、投资收益最大,文中主要聚焦4G业务,实现4G回传承载链路优化.     

基于机器学习的网络状态感知分析方法

为实现业务需求和网络能力的实时精准匹配,需要在网络端引入智能采集处理功能对交互数据进行分析处理,实现对6G网络状态的实时感知和估计预测。设计一种基于机器学习的网络状态感知分析方法,通过隐树模型的多层节点感知能力,能够根据通信网络历史数据,从数据层面对当前的通信网络状态进行量化感知,并对网络后续状态进行初步预测,可以为业务传输层的拥塞控制和移动网络层资源调度提供指导。     

Multicast service protection algorithm based on elastic optical network

With the rapid growth of the network traffic,the elastic optical network (EON) has been proposed as a promising solution due to its high spectrum efficiency and flexible bandwidth provision.Meanwhile,multicast routing and spectrum allocation,and the survivability of the network become more challenging than that in the conventional optical network.The routing for multicast traffic and its protection algorithm in EON was investigated.An integer linear programming (ILP) formulation with the objective to minimize total spectrum consumption was presented.In addition,a heuristic algorithm called multicast sub-tree protection algorithm (MSPA) to achieve sufficient protection and satisfy resources savings was designed.The simulation results demonstrate that comparing with the traditional multicast routing and protection algorithm,MSPA performs well in improving the blocking probability and the spectrum utilization of the network.     

全光网中光码流性能的整体监控

波分复用(WDM)多粒度交换可重构全光网是当前光通信网发展的方向,该文构造了一种实际试验网,提出了一种 眼图法对网中数字光信号进行全面监控的方法,并在自建WDM多粒度交换可重构全光网试验床上进行了演示,结果显示在网络重构等各种条件下均可对网中各波长通道数字信号的信噪比、定时抖动、功率、误码率等进行实时监测控制,该方法对光信号的协议和速率透明且能对各种光性能劣化进行鉴别。     

Traffic Studies for Fast Optical Switching in an Intelligent Optical Network

The optical layer of the transport network is expected in the (near) future to make the transition from a statically configured layer to a fully flexible, automatic and intelligent layer. Such an intelligent optical network (ION) allows to set up (or tear down) bandwidth between two nodes on demand, following a simple request of the client network layer: the so-called switched connections. For successful deployment of these switched connections it is of utmost importance to have a well-educated idea about the granularities of the traffic flows in the optical transport network. Deploying switched connections with a capacity of 10 Gbps to transport a traffic demand with a granularity of a few hundred Mbps does not exactly make efficient use of the network resources. In this paper, the granularity of the traffic demand between US metro areas is investigated for two future points in time, namely 2006 and 2010. For this study we focus on the traffic flows between two metro area entities: the points of presence (PoPs) or the main aggregation points of the customer traffic in a metro area, and the collector central offices (COs) or the nodes a bit further in the metro area, closer to the end-customers. We have found that a significant portion of the total traffic volume at these moments in time will qualify for transport using switched connections with a capacity of 10 Gbps. According to our study, in 2006 around one third of the traffic will qualify for transportation in such 10 Gbps connections between PoPs in different metro areas, while by 2010 this amount will have increased to more than 99%. The traffic granularity between the collector COs, however, will in 2006 still be too small to justify the use of direct 10 Gbps connections, but in 2010 almost three quarter of the traffic could make use of 10 Gbps direct connections from collector CO to collector CO. These results enable us to sketch the expected network evolution scenario and determine the type and size of equipment needed in the different steps of the network evolution. The optical edge aggregation switches will have to be moved deeper into the metro area with time: in 2006 they will be needed at the PoPs, while by 2010 they could be placed at the collector COs.     

绿色IP over WDM网络研究进展

近年来光网络朝着高速率、大带宽的方向迅猛发展,设备数目快速增加导致网络能耗急剧增长。为了降低网络能耗,提高能量利用率,绿色IP over WDM网络的概念被提出,并成为光网络领域的最新研究热点之一。对现有光网络节能方法的研究状况进行综述,从网络设备入手,讨论业务负载和设备能耗的关系,建立了两种能耗模型。基于IP over WDM网络结构,利用数学表达式描述了网络能耗最小化问题。对当前网络级的节能方法进行分类,分析了其基本原理和节能效果,并选取代表性的节能方法进行比较,得出了现有方法存在的局限性和不足,对进一步的研究方向提出了建议。     

Improving throughput of long-hop TCP connections in IP over OPS networks

Optical Packet Switching (OPS) can provide the ever-increasing bandwidth required for Internet traffic and new applications for future networks. However, optical packet loss is the major problem for an OPS network. Moreover, by increasing the number of hops between a pair of ingress–egress switches in an OPS network, optical Packet Loss Rate (PLR) between this pair is increased. Therefore, due to a higher PLR for long-hop TCP connections, the throughput of these connections may be much lower than the short-hop TCP connections. To overcome this problem, it is proposed in this paper to use the retransmission idea in the optical domain not only to increase TCP throughput but also to improve the throughput of multi-hop TCP connections, and also to have a loss-free OPS network. Under retransmission in the optical domain, a copy of the transmitted traffic is kept in the electronic buffers of ingress switches and retransmitted in the optical domain whenever required. Note that the TCP layer has its own retransmission at the client packet level as well. By retransmission of lost packets in the optical domain, TCP would be unaware of the lost client packets, and therefore, TCP would not reduce its sending rate. In this paper, TCP throughput is studied in a bufferless slotted OPS network and the effectiveness of the proposed mechanism is evaluated.

Signaling Schemes for Distributed Connection Management in Wavelength-Routed Optical Mesh Networks

The next-generation optical transport network will evolve from point-to-point connectivity to mesh networking, which can provide fast and automatic provisioning with enhanced flexibility and survivability. Signaling is used to support connection setup, maintenance, and teardown in such a network. In this paper, we study the performance of two hop-by-hop and one parallel signaling schemes in wavelength-routed optical mesh networks. Based on the sequence between optical crossconnect (OXC) switching and signaling message processing, we classify hop-by-hop signaling into two types that comply with the requirements of GMPLS signaling protocols. These two types are forward before switching configuration (FBSC) and forward after switching configuration (FASC). Also, we propose a parallel signaling scheme that is different from the existing hop-by-hop GMPLS signaling protocols. Considering OXC architectures and traffic patterns, we compare the FBSC, FASC, and parallel signaling schemes using simulation experiments, in terms of network blocking probability and reservation time. The simulation data reveal that the performance of a signaling scheme depends on the nature of the signaling as well as the network setting (e.g., the OXC architecture and traffic pattern). We analyze reasons for this result and discuss tradeoffs between these signaling schemes. This work offers some insight into designing an efficient signaling protocol for wavelength-routed optical mesh networks.     

一种新的光因特网网络技术研究

近年来,光技术已能把巨大信息流传送很长一段距离,这一成功使高容量波分多路复用(WDM)系统迅速商业化。WDM技术是在同一根光纤上提供许多“虚”光纤,通过不同的频率传输信号,使网络供应商能在一根光纤中传输许多信号,就像每个信号是在各自不同的光纤中传输一样。光技术的使用强烈地依赖于光网络的类型和需求。近来,光通信技术的研究趋势已集中在新的光通信网络结构和宽带光传输技术两个领域。文中在分析研究光因特网网络模型的基础上,提出一种新型混合模型网络结构。模拟仿真研究结果表明,该技术是可行的。     

软件无线电台自组网技术研究

本文对软件无线电台自组网的研究情况进行了概述,并介绍了一些关键技术的研究进展,包括网络控制管理、路由、网络资源共享、动态负载均衡、软件无线电台网互连等,描述了设计软件无线电台自组网所面临的主要问题,提供了进一步研究软件无线电台自组网的一种思路.     

OTN技术在城域光网络中的应用分析

从城域光网络的概念、业务类型入手,对城域光网络现有技术做了简介,阐述了城域光网络现有技术的不足,并对光传送网（OTN）技术的特点及其在城域光网络中的应用做了一定分析。     

网络编码及其在光组播中的应用研究

组播应用使光网络的带宽资源日趋紧张。网络编码具有提高带宽利用率、提升网络的吞吐量、改善网络负载均衡等优点。分析了网络编码的特点及其编码代价、传统路由面临的问题,讨论了将网络编码引入光组播,优化光组播路由、提高网络吞吐量和资源利用率的研究方法。