基于IPv4/IPv6协议转换技术的IDC过渡方案

由于IPv4地址的短缺,未来网络将向下一代IPv6网络过渡,并且由于IPv4与IPv6的差异,使得这两个网络之间无法互相通信。为在过渡期间,用户能够同时享受IPv4与IPv6两个网络的服务,运营商必须使用IPv4/IPv6网络过渡技术,以达到平滑过渡的目的。文章讨论在教育网中如何通过IPv4/IPv6协议转换技术使IDC机房从IPv4网络平滑过渡到IPv6网络的一个通信场景和解决方案。     

IPv4/IPv6转换网关的SNMP代理设计与实现

基于NAT-PT技术的IPv4/IPv6转换网关部署在IPv4/IPv6网络边缘,用于两网互通.对转换网关提供网络管理功能对保障两网互通有着重要意义.然而,网关所在网络业务流量的复杂性和其基于网络处理器的架构对网络管理的实现提出了挑战.本文提出了一种转换网关SNMP代理的设计方案,定义了NAT-PT MIB,实现了网络处理器环境下分布式MIB的采集并提供了对IPv4/IPv6两网内进行网络管理的支持.     

运营商IPv6演进实践与思考

从IPv4向IPv6演进的顺序来看,必然是网络要先行。当网络具备IPv6能力之后,内容提供商才会提供基于IPv6的业务,用户才会使用IPv6接入网络。对运营商来说,在IPv6还没有大量普及时,最好的方式是通过现网设备的软件平滑升级,开启IPv4/IPv6双栈,在保持对现有IPv4用户和业务最佳兼容的同时提供IPv6接入能力。     

A new 4G architecture providing multimode terminals always best connected services

In recent years, wireless communication technology has undergone a tremendous change. Various radio access technologies have been deployed all over the world. The 4G mobile system was proposed to integrate all of these radio access technologies into a common network called the open wireless architecture (OWA) platform. As one of the main features of a 4G mobile system, always best connected (ABC) services enable users to choose the best available access networks in a way that best suits their needs. A new architecture capable of supporting ABC service is proposed in this study. There are three parts to the proposed architecture. First, a novel access discovery mechanism that integrates service location protocol and location-based service is presented. Second, a new personalized network selection scheme is put forward. Users can select their personalized "best" network by changing weight factors and constraints in a single objective optimization problem. Third, a seamless handover mechanism based on Mobile IPv6 is proposed. The mechanism supports end-to-end quality of service. Through analysis, this architecture demonstrates that it has benefits not only for network operators, but also for users     

4over6:基于非显式隧道的IPv4 跨越IPv6互联机制

IPv6骨干网正在逐步建成并走向实用,纯IPv6的骨干网(如中国下一代互联网:CNGI)已经出现,而已有的大量互联网应用和服务仍存在于IPv4网络中,因此出现了大规模复杂IPv4网络通过IPv6骨干网互联的需求,然而目前没有满足这种需求的过渡机制.本文提出了一种基于IPv6的IPv4网络互联过渡机制框架,对4over6过渡机制框架进行了阐述和分析,并通过原型系统实现,对4over6机制框架进行了原理和功能验证测试.为减小路由开销,提出了ISP独立部署方案,增强了4over6机制框架的可实施性.4over6过渡机制框架具备对网络和端系统透明性、轻型和可自适应动态选路特性,网络管理维护负担小,可适应于大规模、复杂的网络互联等优点.     

Transition to IPv6 in GPRS and WCDMA mobile networks

The limited size and structure of the Internet address space of IPv4 has caused difficulties in coping with the explosive increase in the number of Internet users. IPv6 is a feasible solution for the problems identified with IPv4. Efficient interworking between IPv4 and IPv6 is very important, because IPv4 networks and services will exist for quite a long time. The transition period will be lengthy, and network/terminal equipment supporting both IP versions will be needed during the transition period. Thus, IPv4 to IPv6 transition issues need special care and attention. The three main transition methods are dual IPv4/IPv6 stacks in network elements/terminals, tunneling, and translators in the network. Three transition phases from IPv4 to IPv6 can be identified. These phases are described. Different transition scenarios from the 2G/3G mobile network point of view are also analyzed. Finally, some conclusions are drawn, and some recommendations on the use of transition methods are given     

IPv6业务发展前景与部署策略浅析

在IPv6网络上如何开展业务是目前互联网领域关注的重点之一,本文首先介绍了IPv6支持业务的基本能力和IPv6业务的发展现状,然后从下一代网络的角度探讨了IPv6协议和上层业务系统／平台之间的关系,最后提出了运营商在业务系统中逐渐部署IPv6协议的三种演进思路,即升级现有业务系统逐渐支持IPv6协议,实现不同网络层协议上的业务系统之间的互通,直接建设支持IPV4／IPv6的双栈业务系统,从而实现业务系统向IPv6方向的演进。     

一种基于云平台的下一代互联网新型迁移模型

分析现有接入网络在向IPv6迁移过程中所遇到的各种问题,设计一种新型的基于云平台的下一代互联网迁移模型。该模型通过在城域网边缘部署云计算平台给用户提供虚拟双栈主机,从根本上解决现有接入网络中海量设备以及千万级CPE改造升级所产生的问题,同时,优化了城域网P2P流量模型,极大地减缓了接入网压力。     

Implementation of IPv6 services over a GMPLS-based IP/optical network

In recent days, there has been considerable interest in deploying IPv6-based services. Trial and commercial IPv6 services offering has already begun, especially in Japan, Korea, China, and other parts of the world. At the same time, many service providers have embraced MPLS as the enabler for the required multiservice capabilities of their next-generation packet networks. Also, the widespread deployment of DWDM-based optical transport systems in the core network to satisfy the tremendous need and increase in capacity demand has led network planners to reconsider traditional approaches to provisioning and network restoration, and plan integration of the optical layer into the MPLS infrastructure according to the emerging GMPLS technology. The purpose of this article is to discuss next-generation network architecture evolution and present a detailed architecture for transport of emerging IPv6 services and applications over next-generation GMPLS multiservice backbone networks. This article also presents an implementation and demonstration of this technique for IPv6 transport over a GMPLS backbone network as well as interoperability verification of IPv6 and GMPLS using a GMPLS network testbed.     

在CNGIIPv6上建立诚信安全的P2P环境和分布管理系统

文章指出中国为实施中国下一代互联网(CNGI)计划而大规模布设IPv6骨干网,这为发展P2P应用、建立诚信安全具有分布管理能力的P2P网络环境提供了机会:一方面在CNGI的IPv6网上一开始就可以实行实名制,从而发展建立网络新秩序;另外一方面可以在CNGI上以无缝和持续演进的方式建立智能结点重叠网,以支持P2P应用并提供分布式管理.文章认为CNGI发展的IPv6终端和IPv6用户网(如家庭网、传感器网等)可以通过在现有IPv4有线/无线接入网和城域网中建立IPv6隧道连接到IPv6骨干网P2P平台,以获得足够的通达能力,并在此基础上发展基于P2P的各种新应用.     

Network processors applied to IPv4/IPv6 transition

We describe a high-speed IPv6-IPv4 gateway on an experimental board containing a pair of Intel IXP network processor chips, an FPGA, and a pair of TCAMs. The device is capable of supporting several hundreds of thousands of concurrent TCP/UDP sessions and sustaining close to the line rate on a GbE link. It provides an order of magnitude improvement in packet throughput over an implementation of the same functionality on a commodity PC. IPv6 is beginning to be adopted by organizations and countries that expect to run critically short of IPv4 addresses. Small-scale trials can rely on dual-stock transition mechanisms, in which both an IPv4 and an IPv6 address are assigned to new hosts, which can therefore talk directly to old and new networks. But full deployment must use network address/port/protocol translation (NAPT-PT), in which new hosts are given only IPv6 addresses and must talk through a gateway in order to speak to old networks. The natural location for these NAPT-PT gateways will gradually shift from very local subnets to the edge of a provider network as IPv6 becomes more widely deployed, increasing the demands on the capacity and availability of such gateways. Network processors have the flexibility custom silicon lacks and the speed generic microprocessors lack, and hence are especially well suited for early implementation of network elements such as this gateway between IPv6 islands and the IPv4 ocean. A major challenge in building a scalable middlebox is redundancy support for stateful failover and load balancing, again putting a premium on programmability.     

IPv6关键技术的分析

网络和业务正在趋向于进一步的融合，用一个网络完成电信网、计算机网、广电网的各种业务通信，一直是人们追求的目标。这种融合一定程度上更依赖于统一的网络技术平台的建立，IPv6技术无疑是未来的代表。广电行业在启动数字电视建设的同时，更应该关注IPv6技术的发展。就LPv6关键技术领域，包括高性能：IPv6路由器和交换机系统、IPv6主机和智能终端接入系统、IPv6移动接入系统和：IPv6网络安全系统等相关方面进行介绍。     

面向下一代互联网的接入网演进策略

随着IPv4地址资源的逐渐枯竭,如何引入IPv6是电信运营商非常关注的问题,其中非常重要的问题就是IPv6的引入对接入网的影响以及接入网向下一代互联网演进的方式。本文首先分析了IPv6对接入网的影响和要求;然后结合现有接入网的设备现状,提出了接入网支持IPv6业务的2个主流方式:透传方式和IPv6感知方式;最后,提出了电信运营商接入网面向下一代互联网的演进策略。     

构建更加开放的移动互联网

随着HSPA+等网络的部署,移动互联网业务将进一步丰富,移动通信与互联网将会融合出更大的产业。文章探讨移动互联网的现状、发展趋势,并对运营商部署移动互联网业务提出了相关建议。     

SMS-MIPv6: An End-to-End Mechanism for IPv6 Mobility Management in Mobile Networks

As IP has been extended from core networks to access networks, a mobile network can be considered as an overlay of a traditional cellular network and an IP network. SMS-MIPv6 attempts to integrate mobility management of these two kinds of networks. The basic idea behind SMS-MIPv6 is to exploit existing mobility management in the cellular network (i.e. in the form of well-defined short messages) to locate a Mobile Terminal (MT) in the IPv6 network. We should emphasize that the motivation of SMS-MIPv6 is not to replace or optimize existing mature mobility management schemes. On the contrary, as an entirely end-to-end mechanism for IPv6 mobility management, it provides an alternative mechanism for free peer-to-peer applications such as Voice over IP (VoIP) without support from mobile network operators. We describe the implementation of SMS-MIPv6 in detail and analyze its performance. The evaluation results show that SMS-MIPv6 achieves acceptable performance so that it can be deployed in most current mobile networks. It performs best in terms of signaling cost, data traffic overhead compared with Mobile IPv6 (MIPv6) and Proxy MIPv6 (PMIPv6). Moreover, SMS-MIPv6 can reduce the handover latency significantly, although it is considered as a mobility management scheme for global mobility. However, it increases the session initialization latency due to hybrid binding through the cellular network.     

基于IPv6的移动数据网络发展探讨

IPv6在设计时充分考虑了移动需求,并将移动IPv6作为IPv6的基本组成部分,因此IPv6在移动环境下可更好地支持端到端以及多媒体业务.随着IPv6标准的成熟,移动网络中逐渐引入IPv6也成为通信网络的重要发展方向.本文首先介绍移动数据通信和IPv6技术的发展现状,然后探讨了在移动网络中引入IPv6的策略,并给出了3G网络环境下IPv6地址分配方式以及移动IP技术的发展现状,分析了移动IPv6协议的优点,列举了需要进一步研究的问题,最后给出了结论和建议.     

QoS experiences in native IPv6 networks

Deployment of IPv6 technology in research and commercial networks has accelerated in the last few years. Inevitably, as more advanced services take advantage of the new technology, IPv6 traffic gradually increases. Today, there is limited experience in the deployment of Quality of Service (QoS) for IPv6 traffic in backbone networks that support the Differentiated Services framework. As available software and hardware are designed to handle IPv4 packets, there is a need to accurately measure and validate performance of QoS mechanisms in an IPv6 environment. This paper discusses tests and technical challenges in the deployment of IPv6 QoS in core networks, namely the production dual stack gigabit‐speed Greek Research and Education Network (GRNET) and the IPv6‐only 6NET European test network, using both hardware and software platforms. In either case, we succeeded in delivering advanced transport services to IPv6 traffic and provided different performance guarantees to portions of traffic. The deployed QoS schema was common to IPv6 and IPv4; in most cases both v4 and v6 traffic exhibited comparable performance per class, while imposing no significantly different overhead on network elements. A major conclusion of our tests is that the IPv6 QoS mechanisms are efficiently supported with state‐of‐the‐art router cards at gigabit speeds. Copyright © 2008 John Wiley & Sons, Ltd.     

IPv6技术的中间件、过渡实施和标准化

网络和业务正在趋向于进一步的融合，用一个网络完成电信网、计算机网、广电网的各种业务通信，一直是人们追求的目标。这种融合一定程度上更加依赖于统一的网络技术平台的建立，IPv6技术无疑是代表未来的。广电行业在启动数字电视建设的同时，更应该关注IPv6技术的发展。就IPv6技术的中间件、IPv4向IPv6的过渡和实施、IPv6的典型应用、IPv6技术的标准化等方面进行介绍。     

IPv6网络与业务演进策略分析

随着IPv4地址的加速消耗,IPv4网络和业务向IPv6过渡已经势成必然,但在向IPv6演进的过程中,存在IPv6内容源缺乏,IPv4/IPv6互通困难,网络设备对IPv6支持程度参差不齐等各种问题。电信运营商必须结合自身网络和业务特点,选择合适的过渡技术和策略,平滑地向IPv6演进。本文首先简要介绍各种IPv6过渡技术,然后从电信运营商的角度,分析对比网络和业务向IPv6演进的各种策略,并指出演进过程中存在的一些困难以及解决办法。     

Impact of the evolution of the metropolitan network on the DSL access architecture

Without any doubt, broadband Internet access is one of the most successful services offered by telecom operators today. It gives the operator the potential of offering many new services to residential and business customers, thereby introducing new revenue streams. ATM today provides a solid solution for this. At the same time, packet-based aggregation technologies -especially Gigabit Ethernet are becoming popular for offering connectivity services to business customers. The success of packet-based aggregation technologies is mainly driven by their lower cost compared to established cell-based solutions. This article addresses a number of requirements that must be fulfilled by the access network if it is used to provide multiple services. It will be shown how MPLS and Ethernet can be used in a broadband access architecture. Both meet many of the identified requirements, but still require some standardization before reaching the same maturity as their cell-based counterpart. It will be shown how MPLS technology can be used to seamlessly link cell and packet-centric networks together. This gives operators the possibility to keep the benefits of their existing cell-based infrastructure and smoothly evolve toward a packet-centric approach when the time is right.