Broadband virtual private network signalling

In the corporate voice networks, the virtual private network (VPN) configuration is particularly useful where a shared network infrastructure can be more cost effective and flexible than dedicated leased lines. Current standards for VPN use the international narrowband private signalling system QSIG. Private network signalling standards for broadband networks are also developing rapidly and one can expect that the new emerging signalling systems such as ECMA's BQSIG and ATM Forum's PNNI will play a leading role in the broadband VPN in the future.     

IP micromobility and QoS virtual network testbed

This paper examines issues related to the interaction of QoS and IP micromobility management. More precisely, the inter‐working of a tunnel‐based IP micromobility management with the bandwidth broker QoS control plane is considered. Furthermore, the implementation of the system is detailed and it is tested using a virtual network testbed, based on ‘user‐mode‐Linux’. Finally, as a proof of concept the signalling between the different entities is examined with the protocol analyser ‘ethereal’. Copyright © 2007 John Wiley & Sons, Ltd.     

虚拟专用网络在计算机网络信息安全中的运用分析

文章首先对VPN技术的理论和特征进行概述,并在此基础上,罗列国际常用的VPN技术类型.最后结合个人经验对虚拟专用网络在计算机网络信息安全中的有效使用路径开展了逐一分析,希望可以为从事相关领域工作的人员提供有效的帮助.     

虚拟专用网络技术在计算机网络信息安全中的应用探讨

为了更好地实现计算机网络信息安全的保护管理,引入的虚拟专用网络技术发挥了重要的作用。文章就这种新的虚拟专用网络技术在计算机网络信息安全中的应用情况进行了深入的探讨分析,以及进一步分析了虚拟专用网络技术在计算机网络安全中的应用前景,希望对计算机网络信息的安全有很好的促进和保护作用。     

虚拟专用网技术在雷达情报网中的应用及解决方案

为增强雷达情报网的生存和再生能力,在特殊情况下,雷达情报信息有必要通过公用网络传输.为保障数据在公网中传输的安全性,提出基于虚拟专用网技术组建雷达情报网的方案,在可行性分析的基础上,设计了网络拓扑结构,采用L2TP和IPSec隧道协议对网络进行了具体架设.     

Layer 1 virtual private network management by users

The layer 1 virtual private network (LlVPN) technology supports multiple user networks over a common carrier transport network. Emerging L1VPN services allow: L1VPNs to be built over multiple carrier networks; L1VPNs to lease or trade resources with each other; and users to reconfigure an L1VPN topology, and add or remove bandwidth. The trend is to offer increased flexibility and provide management functions as close to users as possible, while maintaining proper resource access right control. In this article two aspects of the L1VPN service and management architectures are discussed: management of carrier network partitions for L1VPNs, and L1VPN management by users. We present the carrier network partitioning at the network element (NE) and L1VPN levels. As an example, a transaction language one (TL1) proxy is developed to achieve carrier network partitioning at the NE level. The TL1 proxy is implemented without any modifications to the existing NE management system. On top of the TL1 proxy, a Web services (WS)-based L1VPN management tool is implemented. Carriers use the tool to partition resources at the L1VPN level by assigning resources, together with the WS-based management services for the resources, to L1VPNs. L1VPN administrators use the tool to receive resource partitions from multiple carriers and partner L1VPNs. Further resource partitioning or regrouping can be conducted on the received resources, and leasing or trading resources with partner LlVPNs is supported. These services offer a potential business model for a physical network broker. After the L1VPN administrators compose the use scenarios of resources, and make the use scenarios available to the L1VPN end users as WS, the end users reconfigure the L1VPN without intervention from the administrator. The tool accomplishes LlVPN management by users     

一种新型VPN网络设计及QoS性能仿真

通过对现有各专网方案所存在问题及未来数据网络演进趋势的分析,以ATM- MPLS重叠网络的方式设计了一种新型VPN方案,并提出在现网的具体构建策略,证明了该方案具有现实部署的可行性.通过OPNET实现语音、数据及视频等多业务的仿真模拟,其中以数据业务响应时间作为量化指标,仿真结果表明该新型网络在高负载下响应时间在0.6s以内,且不累积拥塞,具有类似ATM的技术优势,为宽带网络演进提供了一种解决思路.     

一种光虚拟专用网管理实现方案

光虚拟专用网(OVPN)是自动交换光网络(ASON)的一种新兴的增值业务,ASON控制平面使得OVPN的实现更加灵活。文章对OVPN的管理方案进行分析,提出了一种基于WBEM(Web-based enterprise management)的管理体系结构,并对OVPN 的通用信息模型(Common Information Model)进行了分析设计。     

一种光虚拟专用网管理实现方案

光虚拟专用网（OVPN）是自动交换光网络（ASON）的一种新兴的增值业务,ASON控制平面使得OVPN的实现更加灵活.文章对OVPN的管理方案进行分析,提出了一种基于WBEM（Web-based enterprise management）的管理体系结构,并对OVPN的通用信息模型（Common Information Model）进行了分析设计.     

虚拟专用网络技术在计算机网络信息安全中的应用

随着我国综合国力的日益强盛和科学技术的日新月异,计算机网络信息安全也越来越被人民所关注和重视,今年来,利用计算机网络信息管理的漏洞,来窃取人们信息或采取的作案手段越来越多件,所以计算机网络信息安全已经是一项迫在眉睫的任务。在计算机网络信息安全中,虚拟专用网络技术发挥了重要的作用。本文主要分析了虚拟专用网络技术的发展现状,以及它在计算机网络信息安全中的应用和市场前景,希望能对计算机网络安全方面的探索和研究提供一些理论方面的帮助。     

面向业务和网络协同的未来IP网络架构演进

IP技术作为互联网的技术基础,在今后5～10年如何发展是通信行业面临的关键问题。分析了传统IP网络架构的成功与不足,提出未来IP网络既要继承传统IP技术的设计原则,比如端到端原则和分层解耦原则,又要解决现有IP网络中业务和网络过于割裂的问题。从网络演进和未来业务需求的角度出发,认为未来IP网络的核心问题是要加强业务和网络的协同,提出了改进后的IP网络设计原则“横向：服务化网络赋能的端到端架构,纵向：智能控制面支撑的分层模型”,并且基于此原则提出了未来网络的参考架构。     

虚拟专用网的生存性方案

光虚拟专用网(OVPN)是光网络的主要服务模式之一,OVPN的生存性是其业务得以开展的前提和基础。首先对虚拟专用网的概念作一介绍,随后对OVPN生存性的问题进行了分析,在此基础之上给出了OVPN生存性的基本模型,最后讨论了三种不同的OVPN生存性路由方案,并对其性能进行了分析和对比。     

IP数据业务在双向HFC上的传输

介绍了HFC上IP数据业务传输的特点。根据DOCSIS1．0／1．1规范详细地讨论了光纤同轴混合网上数据传输中信道要求、调制技术、电缆调制解调器的初始化以及接收和发送数据。     

Commercial models for IP quality of service interconnect

Interconnection of IP QoS capabilities between networks releases considerable value. In this paper we show where this value will be realised. We give technical and economic arguments for why QoS will be provided in core and backbone networks as a bulk QoS facility incapable of distinguishing or charging differentially between sessions, while between edge networks a vibrant mix of retail QoS solutions will be possible, including Internet-wide per-flow guarantees.We outline cutting edge research on how to co-ordinate QoS between networks, using a session-based overlay between the edges that will extract most surplus value, underpinned by a bulk QoS layer co-ordinating the whole. We survey today’s interconnect tariffs and the current disconnected state of IP QoS. Then we describe a commercial ‘model of models’ that allows incremental evolution towards an interconnected future.The paper covers intertwined engineering and economic/commercial issues in some depth, but considerable effort has been made to allow both communities to understand the whole paper.     

IP/ MPLS over WDM网中考虑QoS的VPN业务设计

本文研究了在IP／MPLS over WDM网络中支持不同QoS要求的VPN业务的逻辑拓扑设计问题。对于给定的网络物理拓扑和业务需求矩阵，本文提出，基于不同时延要求的VPN业务逻辑拓扑设计可以运用两种方法加以解决。一为基于迭代的线性规划方法，适合于规模较小的网络。另一个为启发式算法，可运用于网络规模较大的环境。对比仿真结果表明，启发式算法不但较好地解决了不同QoS要求的VPN业务的选路和波长分配问题，还较好地降低了链路的最大负载。     

IP over WDM网络中一种新型虚拓扑构造算法

对IP over WDM的虚拓扑设计算法进行了研究，选择网络整体流量的均衡性作为优化目标，提出了一种新型的虚拓扑构造算法。在算法中，选择负载分布方差作为评价流量均衡性的指标，并给出其定义和计算方法。主要针对拥塞概率性能，在光层和IP层将提出的新型虚拓扑构造算法与其他算法进行比较。在光层的算法比较部分，选择负载均衡启发式路由算法（RLBH，routing with load balancing heuristics）与提出的算法进行比较；在IP层的算法比较部分，选择固定路径最小拥塞路由算法（FPLC，fixed-path least-congestion）与提出的算法进行比较，并对比较结果进行了讨论。比较结果显示在拥塞概率性能方面，提出的新型虚拓扑构造算法优于RLBH算法和FPLC算法。     

Migration cost optimization for service provider legacy network migration to software-defined IPv6 network

This paper studies a problem for seamless migration of legacy networks of Internet service providers to a software-defined networking (SDN)-based architecture along with the transition to the full adoption of the Internet protocol version 6 (IPv6) connectivity. Migration of currently running legacy IPv4 networks into such new approaches requires either upgrades or replacement of existing networking devices and technologies that are actively operating. The joint migration to SDN and IPv6 network is considered to be vital in terms of migration cost optimization, skilled human resource management, and other critical factors. In this work, we first present the approaches of SDN and IPv6 migration in service providers' networks. Then, we present the common concerns of IPv6 and SDN migration with joint transition strategies so that the cost associated with joint migration is minimized to lower than that of the individual migration. For the incremental adoption of software-defined IPv6 (SoDIP6) network with optimum migration cost, a greedy algorithm is proposed based on optimal path and the customer priority. Simulation and empirical analysis show that a unified transition planning to SoDIP6 network results in lower migration cost.     

Priority-based minimum interference path multicast: routing algorithm in optical virtual private network

While the “Virtual Private Network (VPN) over Internet” is cost-effective and flexible, it suffers from the difficulty of providing adequate transmission capacity for high bandwidth services. Hence a Dense Wavelength Division Multiplexing (DWDM) based “Optical VPN (OVPN)” technology has been regarded as a good alternative for realizing the future VPN services. To improve the transparency and data rate of OVPN, it is critical to consider the problem of Routing and Wavelength Assignment (RWA) for transmission capacity utilization. This paper proposes a Priority-based Minimum Interference Path Multicast Routing (PMIPMR) algorithm, a new routing algorithm which finds alternative routes based on node priorities and Virtual Source (VS) nodes that has both splitting and wavelength conversion, and then chooses a path that does not interfere with potential future multicast session requests when congestions occur in the network. The PMIPMR algorithm reduces blocking rate significantly and increases the wavelength utilization by avoiding congestion in future multicast session requests. We measured the performance of the proposed algorithm in terms of blocking rate and the resource utilization. The simulation results demonstrate that the PMIPMR algorithm is superior to the previous multicast routing algorithms using the Capability-based-Connection algorithm based on Capability-based-Priority and Spawn-from-VS methods.     

Virtual private network services: scenarios, requirements and architectural constructs from a standardization perspective

This article describes scenarios, general requirements, and architectural constructs for the emerging category of services known as virtual private networks. According to the adopted reference models, the principal architectural choices in the service provider solution space and current VPN-related standardization initiatives are introduced.     

虚拟专用网络安全通信机制的研究与实现

研究了基于IPSec的虚拟专用网络安全通信机制,详细地讨论了虚拟专用网络中的数据源认证和完整性保护算法、反重放算法的原理,并给出其相应的编程实现。同时对密钥交换技术作了深入的研究,阐述了如何通过一系列参数的协商在非安全的公共IP网络中建立安全通信的密钥交换机制的详细过程,给出了一种基于Linux操作系统的客户机／服务器IKE密钥交换编程实现。对IPSec安全特性作出了分析,并对今后研究发展的方向作了进一步的展望。