Ethernet OAM: key enabler for carrier class metro ethernet services

The onset of Ethernet as a metropolitan and wide area networking, technology has driven the need for a new set of operations, administration, and maintenance protocols. Service provider networks are large and complex with a wide user base, and they often involve different operators that must work together in order to provide end-to-end services to enterprise customers. With enterprise end customer demands ever increasing, so have the requirements on service provider Ethernet networks increased, particularly in the areas of availability and mean time to repair. Ethernet OAM addresses these areas and more, and is a tool that translates directly to the competitiveness of the service provider. Ethernet OAM is a broad topic, but this article focuses on three main areas that are most in need by service providers and are rapidly evolving in the standards bodies: Service OAM, Link OAM and Ethernet LMI. These OAM protocols have unique objectives but are complementary to each other. Service OAM provides monitoring and troubleshooting of end-to-end Ethernet service instances, while link OAM allows a provider to monitor and troubleshoot an individual Ethernet link. There are of course many different ways to provide this type of functionality, but fortunately standards bodies such as ITU Study Group 13, IEEE 802.3 Clause 57 (formerly 802.3ah), IEEE 802.1ag Connectivity Fault Management, and the Metro Ethernet Forum are all driving toward consistent recommendations and standards for Ethernet OAM.     

城域网专用的光以太网

光以太网正蓄势待发，力图冲破最后的障碍，大力发展具有经济效益的高速城域网。个案根据对多个大型城域的地理和人口统计。以提供一系列基于以太网的企业服务为前提，通过对经营收入、成本和运营现金流的分析，对光以太网、以太网络／DWDM和新一代同步光纤网络等三种城域网方案进行了对比。个案对光以太网的经济效益进行了全面的衡量，为城域网采用光以太网提供了肯定的证据。     

充满前景的光以太网

为了与呈爆炸式增长的带宽需求保持同步,网络容量每年都在成倍地增加。传统的为传送语音流量而设计的骨干网络已不能满足这种需求。出于经济的原因,加上网络技术的快速发展,将来的网络应是IP、光纤及高速以太网的融合,即光以太网。本文分析了光以太网的技术优势及发展前景。     

Ethernet ring protection for carrier ethernet networks

Ethernet technologies are rapidly gaining importance as a prevailing solution for carrier networks. Ethernet ring protection switching, defined in ITU-T Recommendation G.8032, provides a means of achieving carrier network requirements for ring network topologies. This article outlines the novel concepts in this Ethernet ring protection switching mechanism and discusses the fundamental operating principles by which the automatic protection switching (APS) protocol works. In addition, several feature enhancements in protection behavior and solutions being considered for the next phase of standardization are discussed.     

Ethernet as carrier transport infrastructure

New innovations in the Ethernet space promise to significantly enhance both the scalability and capability of Ethernet as a networking technology. This article outlines how the convergence of hierarchy, OAM functionality, and enhanced forwarding capability combine to permit Ethernet to assume a much larger role in carrier networks with substantial economic and operational benefits.     

光以太网:LAN与WAN终于对接

迄今为止,光网络投资主要是在长途网络和城域核心网络的建设上。而如今,网络服务提供商所面临的主要挑战是,如何把这些光网络的能力以及灵活性延伸到光网边缘来解决接入段的瓶颈问题。以太网将是实现这一战略目标的关键。新的服务模型以太网是一种基于竞争策略和“尽力而为”的LAN技术。从早期的IEEE 802.3标准的开发至今,以太网在兼容性方面已达到了即插即用的水平,从而使其成为一种到处可用的网络技术。以太网几乎支持全频段的传输速率,包括10/100Mb/s、1Gb/s、和10Gb/s。而且就技术和成本而言,是任何WAN所无法比拟的。长期…     

Ethernet services over mobile WiMAX

Ethernet services represent a steadily growing portion of the fixed telecommunication market. To enable the provisioning of Ethernet services over IEEE 802.16e, the mobile WiMAX network architecture supports transparent Ethernet transport as an optional extension to the IP services architecture. Ethernet support is tightly aligned to the IP services network model, and leverages many data path and control plane functions from its IP sibling to keep the implementation and operation overhead low for the Ethernet extension. Mobile WiMAX provides IP services as well as Ethernet services over the same mobile access network. The intrinsic mobility support may create new deployment opportunities for Ethernet services. Initially, the Ethernet extension may be mostly used to realize wireless access for DSL networks based on the same network interfaces defined for the wired Ethernet-based DSL aggregation.     

光以太网的业务实现

语音、视频网络的数据化以及多媒体通信和多媒体交互信息的大量应用使数据网的带宽需求呈爆炸性增长.数据网络面临比以往任何时候都更为严峻的挑战.光技术的发展和应用为数据网络应对上述挑战提供了解决方案,即向全光网络演进,而在其中,光以太网扮演了重要的角色.     

光以太网及其解决方案

１摇光以太网的概述现今网络的发展趋势是：光网络从广域网和城域网向本地网渗透;随着１０G以太网标准（IEEE８０２郾３ae）即将形成,以太网的分布得以从局域网延伸至城域网和广域网。光网络与以太网的融合和发展形成了光以太网,因此,光以太网集中了两者的优点,如以太网的应用普遍、价格低廉、组网灵活以及管理简单,和光网络的可靠性高和容量大等。光以太网的高速率、大容量消除了存在于局域网和广域网之间的带宽瓶颈,将成为未来融合话音、数据和视频的单一网络结构。光以太网的核心是利用光纤的巨大带宽资源和以太网的成熟、易用…     

光以太网技术综述

本从光以太网提供的连接业务，光以太网的特点，光以太网的优势，光以太网弹性分组环技术，基于以太网的无源光网络以及光以太网的应用等方面，详细地介绍了光以太网技术。     

能提供VPN业务的光以太网

城域网作为骨干网和广域网在城市范围内的延伸,连接成千上万的城市用户,是提供新一代话音业务和数据业务的关键所在。由于要在城域网的边缘部署、设置和管理大量设备,所以城域网代表了运营商的大部分资本预算和经营预算。从目前中国电信、网通、联通已经实施和应用的城域网结构来分析,由于网络采用第三层的IP路由技术,网络中部署了大量的结构复杂的路由设备,这些设备大大加重了运营商的前期投资成本,也造成了数据业务投资大、收入低的现象。因此,如何降低城域网的运营成本是广大运营商关注的主要方面。许多业内人士认为成本经济的…     

光纤联网：开发高级业务的工具

曾被人们认为未来才会出现的有线业务，如交互VOD(视频点播)、快速因特网接入和IP电话很快就会成为今日的现实。这些业务的迅速发展对其传输渠道——光纤同轴电缆混合网(HFC)有着越来越多的需求。     

Ethernet as a carrier grade technology: developments and innovations

Recent innovations in Ethernet networking technology are enhancing both the scalability and capability of Ethernet as a carrier-grade transport technology. This article explains four main innovations recently added to Ethernet, improvements related to scalability, OAM functionality, and enhanced forwarding capability in order to permit Ethernet to assume a much larger role in carrier networks with substantial economic and operational benefits.     

基于多波长光标记交换技术的城域光以太网

在多波长光标记交换技术的基础上,结合当前应用广泛的光以太网技术,提出了构建城域光标记交换以太网的构想。在国际上首次搭建了多波长光标记交换试验床,成功完成了高速多媒体视频信号和摄像头捕捉信号的演示,实现了微秒量级的光标记包头和光包的可编程组装拆分。先进的多波长光标记交换加上商用化的光以太网技术,成为未来城域网建设的一种理想的组网方案。     

新一代的EPON网络管理系统

针对EPON系统是基于以太网的宽带无源光网络的特点和系统结构,提出了两种网络管理方式,然后介绍了EPON网络管理所需完成的功能。     

光以太网弹性分组环技术

弹性分组环技术综合了以太网的的成本和SDH的可靠性的优点,既可以承载具有突发性的IP业务,又能支持语音传送,是城域网较理想的解决方案。     

以太网无源光网络中的突发模式

以太网无源光网络可以实现低成本、远距离的宽带接入。本阐述了以太网无源光网络(EPON)的结构、原理并提出上行突发模式方案。     

QoS Control Schemes for Two-Stage Ethernet Passive Optical Access Networks

Ethernet passive optical networks (EPONs) have emerged as the one of the most promising candidates for next-generation access networks. These new architectures couple low-cost optics with advanced edge electronics to offer vastly improved scalability over competing digital subscriber line and cable modem offerings. This paper proposes several novel architectural enhancements for EPON, which will help increase the viability of optical access over a broader range of subscriber access scenarios. Specifically, this paper proposes a two-stage EPON architecture that allows more end-users to share an optical line terminal link, and enables longer access reach/distances (beyond the usual 25 km distance). In addition, a new dynamic bandwidth allocation (DBA) algorithm is proposed to effectively allocate bandwidths between end users. This DBA algorithm can support differentiated services in a network with heterogeneous traffic. We conduct detailed simulation experiments to study the performance and validate the effectiveness of the proposed architecture and algorithms.     

以太网无源光网络中的时间标签法测距

基于千兆以太网的无源光网络将千兆以太网与无源光纤接入的优势相结合,实现低成本的高速、远距离接入。针对EPON系统上行链路多个ONU共享带宽的树型拓扑结构,为实现EPON系统上行TDMA接入,提出了时间标签法测距方案,论述了方案的可行性并指出其优点。     

EPON中组播协议的实现

探讨了EPON中实现IP组播业务的方法,详细描述了OLT和ONU对IP组播业务数据报的处理过程,以及对EPON用户终端设备加入、离开组播组的IGMP协议帧的处理过程