基于SDN的跨数据中心承载技术

互联网产业的发展和云计算的兴起催生了跨数据中心互联的需求,而软件定义网络技术为解决数据中心互联的网络瓶颈提供了重要途径.首先介绍了几种常用的数据中心互联技术,分析了SDN的技术优势,然后提出了一种基于SDN的运营商数据中心互联承载技术方案,并阐述其实现思路.该方案可实现DC间的网络虚拟化,能够提供用户业务定制、网络自动开通、任意虚拟机间的策略隔离、流量调度、用户就近访问、DC间的容灾备份等业务功能.     

移动自组织网与有线网融合技术研究与展望

随着移动自组织网络(MANET)组网技术的不断成熟,MANET路由协议与传统Internet路由协议的融合已经成为网络互联的重要内容,成为影响组网效率的决定性因素.本文分别对移动自组织网络作为末端网和承载网的互联技术进行了研究,并在此基础上提出了基于无线栅格网络(wireless mesh networl,WMN)结构的未来移动互联技术的演进方案,对WMN的路由协议进行了有意义的探讨.     

“沃互联”统一认证技术研究

近年来,网络用户信息泄露事件愈演愈烈,为保障网络用户个人数据安全,研究了网络场景下用户电子账户所面临的安全风险与威胁,分析了网络用户账号相关安全需求,提出了一种网络强身份认证方式——“沃互联”统一认证方案,该方案是以手机号码为用户唯一身份标识,为网络业务提供商提供统一的安全认证能力,使用户获得安全、便捷的用户认证和授权体验.     

多动的办公室

移动办公出现以来的又一个新兴概念,是经济、科技、社会三者发展进步的共同产物。通过无线互联平台(MIPTM)及其应用系统的支撑,移动Office已经成为一种能够使用户获得随时随地、简便快捷、安全可靠、价格合理的通信和办公能力的解决方案。通过移动Office和WAP技术,人们可以在任何时间任何地点办公,可以从移动电话、掌上电脑、PDA等终端设备上收发数据,邀游于Internet之上。无线互联平台(MIP^TM),将因特网和移动通信网络有机地“粘合”起来,为无线互联提供强大的应用支撑能力,是实现移动Office重要的网络支撑技术。     

下一代无线网络的移动性管理

在下一代无线网络中,用户可以任意地在不同的无线接入网之间切换。移动IP(MIP:Mobile IP)是当前无线IP网络中的移动性管理协议。但是移动IP协议难以为网络的服务质量(QoS:Qualicy ofService)提供保障。将多协议标记交换(MPLS:Multiprotocol Label Switching)和MIPv6结合的技术是解决这个问题的方案之一。本文介绍了MPLS和移动IP技术的基本原理,研究了基本移动MPLS和分层移动MPLS的实现方案,并基于HMIPv6 over MPLS网络结构介绍了一种为无线网络提供Qos支持的实现方案。     

下一代移动网络业务技术研究

下一代移动网络与下一代固网网络一样,是业务驱动的网络,业务开发的好坏直接决定基础网络的利用率、为用户提供的业务种类和由业务带来的利润大小,可以说要想让电信走出低靡,业务必须先行。一、移动网络的业务分类1. 3GPP业务分类第三代移动通信网络不再定义业务本身,而是对业务生成机制进行明确的规定,并积极创建与第三方之间的标准开放接口和终端的应用环境,如图1所示。(1)业务类型在电路域,基本业务分为电路型电信业务、承载业务和补充业务;在分组域,提供IP承载业务。短消息、非结构化补充业务数据(USSD)、用户到用户信令(UUS)也可…     

智能移动生活服务平台的研究

随着3G商用进程的不断加快,移动互联成为人们新的商务模式,通过移动终端获取信息产品和服务具有现实意义.文章通过对移动互联商务平台方案应用场景的描述,对用户行为模式的智能识别、智能搜索和二维码识别等技术方案进行了分析和研究,提出了针对用户建立个性化需求模型开发方案的设计,使用户以更快捷的方式找到自己需要的信息,同时为企业达到良好的商业推广效果.     

WLAN-3GPP融合架构中网络选择机制优化

为了综合利用WLAN与3GPP移动网络各自的优势,3GPP R9定义了3GPP与WLAN网络融合体系架构,并在3GPP与WLAN网间选择中引入接入网发现和选择功能单元(ANDSF)网络选择机制。文章在研究WLAN-3GPP融合参考体系架构与现有ANDSF网络选择机制基础上,分析了基于ANDSF网络选择机制的不足,提出了一种基于用户业务感知与ANDSF相结合的WLAN-3GPP融合架构网络选择方案,为融合架构中3GPP与WLAN网络切换提供了基础,有效提高用户体验与网络控制能力。     

智能网网络演进策略的研究

智能网(IntelligentNetwork)是为PSTN网络提供增值业务的主要解决方案,本文针对业务需求,结合中国电信的智能网现状提出了智能网网络改造的方案。阐述了智能网与Internet互通、增强计费功能、SCP互联、用户属性触发等问题的解决方案。同时,论述了为NGN用户提供智能网业务的实现方式。     

基于智能终端辅助的ANDSF网络选择机制增强

随着LTE与WLAN热点的大规模建设部署,为了综合利用WLAN与3GPP移动网络各自的优势,3GPPR9定义了3GPP与WLAN网络融合架构体系,并在3GPP与WLAN网间选择中引入ANDSF(Access Network Discovery Support Functions,接入网发现和选择功能单元)网络选择机制。本文在研究3GPP-WLAN融合参考体系架构与现有ANDSF网络选择机制基础上,针对ANDSF网络选择机制的不足,提出了一种基于智能终端用户业务感知与ANDSF相结合的网络选择增强方案,为融合架构中3GPP与WLAN网络切换提供了基础,有效提高用户体验与网络控制能力。     

Voice over ATM: an evaluation of network architecture alternatives

This article describes eight application scenarios in which there is a business case for voice over ATM. It then evaluates alternative network architectures for implementing the required network functionality. The article incorporates much of the ongoing work of the ATM Forum and the ITU, but does not restrict itself to standards and implementation agreements. In addition, it evaluates nonstandardized alternatives for ATM transport of voice traffic. There are two main areas: N×64 kb/s structured data transfer, also known as composite cell transport-a network operator may aggregate individual voice calls into N×64 kb/s blocks for transport to an intermediate point in the network. At that point the individual calls need to be remapped into new M×64 kb/s blocks for the next stage of their transport. Architectural alternatives and advantages of remapping are investigated. Interworking of signalling is of two types: network interworking, in which the end users are connected to non-ATM networks and an ATM network is used for backbone transport; and service interworking, in which an ATM user is connected to a non-ATM user. Functionality and architectural alternatives for network and service interworking are evaluated     

Internetworking connectionless and connection oriented networks

The use of connection-oriented (CO) networks for the transport of IP traffic is seen to have value to both users and service providers. Given the expectation that most endpoint-generated traffic will be in the form of connectionless (CL) IP datagrams, we address the problem of how to internetwork a CL (IP) network with a CO network. CO networks can be packet-switched or circuit-switched. Examples of packet-switched CO networks include ATM and MPLS networks, in which resource reservations are made at the ATM or shim layer, and IP-switch-based networks, in which resource reservations are made at the IP layer. Examples of circuit-switched networks include SONET/SDH and WDM networks that consist of programmable optical crossconnects. We consider the internetworking problem for two modes of operation of CO networks: provisioned, in which connections are set up a priori, and switched, in which connections are set up on demand. The main focus of this article is on the more complex problem: the internetworking of CL IP networks with CO networks operated in a switched mode. Our solution consists of (i) interworking user plane protocols with protocol conversion in some cases instead of always using protocol encapsulation, (ii) interworking routing protocols by either simply having gateways know routing information of both networks or having all nodes know routing information of both networks, and (iii) interworking signaling protocols by using application- or transport-layer end-to-end handshakes to trigger connection setups through the CO network. We demonstrate throughput improvements with our integrated routing interworking scheme over the MPOA IP-ATM internetworking solution for two example networks     

Resource management for QoS support in cellular/WLAN interworking

To provide mobile users with seamless Internet access anywhere and anytime/ there is a strong demand for interworking mechanisms between cellular networks and wireless local area networks in the next-generation all-IP wireless networks. In this article we focus on resource management and call admission control for QoS support in cellular/WLAN interworking. In specific, a DiffServ interworking architecture with loose coupling is presented. Resource allocation in the interworking environment is investigated/ taking into account the network characteristics, vertical handoff, user mobility, and service types. An effective call admission control strategy with service differentiation is proposed for QoS provisioning and efficient resource utilization. Numerical results demonstrate the effectiveness of the proposed call admission control scheme.     

Services in interworking 3G and WLAN environments

Interworking WLANs and 3G mobile networks are expected to provide ubiquitous wireless communications at high data rates and a large variety of services with variable bandwidth and QoS requirements, across a wide range of propagation environments and mobility conditions, using dual mode terminals. The interworking of the two networks is a major step toward a new generation of wireless networks in which other radio technologies are also be integrated. In this article we present possible architectures that enable the interworking of 3G and WLAN networks. We then address the capabilities of various terminal types and describe future services in the interworking environment. Finally, we present market forecasts on terminal and service demand growth.     

An IP transport and routing architecture for next-generationsatellite networks

Over the past several years, a number of new satellite systems have been proposed to provide high-speed Internet and multimedia services to businesses and home users. These proposals have been driven by the desire of network operators to reach end users that do not have cost effective access to other alternatives such as fiber, DSL, and cable, and by the availability of new spectrum (Ka-band) for use by new satellite services. The proposed systems generally employ multiple high-power spot beams, an onboard fast packet switch, and a demand-assigned multiple access scheme to provision IP-based services. In this article we concentrate on a geosynchronous satellite system where packet transport and switching within the satellite system are based on ATM. We describe an IP/ATM interworking and IP routing architecture that is driven by three main requirements: (1) the ability to support ATM SVCs between hundreds of thousands of satellite terminals by a single ATM switch located onboard; (2) a scalable IP routing architecture that does not result in large volumes of routing traffic to be transported over the satellite; and (3) the ability to segment the satellite terminals for routing and administrative control by ISPs and enterprise networks     

Telecommunications management network (TMN) architecture andinterworking designs

The authors discuss data communications networks (DCNs) used by operating telephone companies to interconnect large numbers of telecommunications network elements with operations systems and workstations to support and manage telecommunications networks, referred to by the international telegraph and telephone consultative committee (CCITT) as a telecommunications management network (TMN). The TMNs can include different types of DCNs such as private lines, circuit-switched networks, packet-switched networks, and integrated services digital networks (ISDNs). These can be divided into two classes: connection-mode and connectionless-mode networks. The authors briefly consider TMN concepts and implementation architectures. They then focus on TMN internetworking design alternatives, issues, and protocol stacks, in order to provide data network designers and implementors with the necessary fundamentals in considering and choosing interworking solutions for TMN applications     

Mobility management alternatives for migration to mobile Internet session-based services

Session-based Internet protocol (IP) applications, such as Internet telephony, are an important component of the emerging mobile Internet. The ubiquitous availability of these services is critical to the success of the mobile Internet. Because all-IP networks will be deployed in phases and current mobile telecommunication systems will be in operation for decades to come, the interworking and migration between current network services and all-IP services is a key problem. In this paper, we address seamless roaming for session initiation protocol-based services across current cellular telecommunication networks and emerging all-IP wireless networks, such as those using third-generation and WiFi networks. We present an abstract mobility model, and map this model to three basic approaches for supporting seamless mobility: a master-slave approach, a federated system, and a unified approach. We discuss the challenges and implementation of an instance of the unified mobility management approach, called the Unified Mobility Manager, and then compare the tradeoffs of the three systems using a comparative performance analysis. We conclude that unified mobility management is most efficient if a great deal of interworking is required, and as more users invoke IP-based services; the federated approach is efficient when a single network technology is dominant and data access is limited, but requires sharing of data across networks; the master-slave approach is the least efficient, but is easy to introduce if the number of network types is small.     

Personal Network (PN) Applications

The applications of PN will be realised under many scenarios where users can have access to their personal network all the time. This network will enable the user to share critical information, play games, control their home remotely, etc. All this will be achieved with seamless interworking and handover between networks and user devices. This paper presents an array of use case scenarios that validates the ubiquitous usage of PN.     

WLAN与3GPP无线互操作研究进展与展望

终端如何在3GPP与WLAN中选择最优网络接入并进行业务分流是WLAN与3GPP互操作中需要解决的重要问题。传统3GPP与WLAN互操作主要集中在核心网层面,无法考虑无线网络负载,容易造成网络负荷不均,用户体验降低。3GPP R12阶段在RAN2开展了WLAN与3GPP无线互操作研究,定义了一系列无线接入网辅助参数和无线接入网规则以增强WLAN与3GPP在无线的接入网选择和业务分流方案,有效提高了用户体验以及运营商对于WLAN的控制能力,为WLAN与3GPP网络深入融合提供解决方案。     

TCP/IP enhancements for satellite networks

With the emerging market for high-mobility remote access broadband services, satellite networks are becoming increasingly popular. Although the ubiquitous TCP/IP protocol is widely used to provide reliable data delivery in terrestrial networks, it faces many challenges in satellite environments. These stem from the inherent features of satellite channels, such as large delays, increased error rates, and bandwidth asymmetry. To address these concerns, a variety of solutions have been proposed. These include direct TCP enhancements to better tune the TCP/IP stack and additional selective acknowledgment mechanisms. Other proposals use advanced interworking to reduce sensitivity to various channel features. Examples include multiple TCP sessions, link-layer interworking, and ACK control schemes. Improving onboard satellite features (buffer management, flow control) can also provide benefits for TCP/IP transport. The objective of this article is to present the various solutions and discuss their possible trade-offs. Overall, there exists a rich set of alternatives to meet the challenges in this important arena