Building Traversing NAT IPv6 Tunnel Gateway System Relies on Netfilter/Iptable Framework

The transition from IPv4 to IPv6 is doomed to be a long process. The network Address translation （NAT） technology is used very popularly in IPv4 network to make up the shortage of network address. It is a desiderated problem to make the users behind NAT gateway to access to IPv6 networks. By studying the transition technology from IPv4 to IPv6 and introducing NAT technology in IPv6, a scenario is put forward through 6to4 tunnel The scenario is implemented and the gateway system＇s performance is analyzed.     

Strategies of Transition to IPv6

he consumption of IPv4 address resources is delayed with the support of Classless Inter-Domain Routing (CIDR) and Network Address Translation (NAT) technologies. However, a high-speed development of the Internet, tremendous demands for broadband access and the predictable construction of the 3G network and Next Generation Network (NGN) all need huge address space. Therefore, it is inevitable to introduce IPv6 and deploy IPv6-based networks on a large scale. IPv6 has been developing …     

Research and Design of IPv6 Network Management and Operations Support System

1 Status Quo of IPv6 Network Development he advantages of IPv6 over IPv4 are expanded addressing capabilities, improved manageability, security, mobility, and Quality of Service (QoS). Actually, IPv6 is designed to take the place of IPv4 used on current Internet[1]. As the trend goes, more IPv6-based Next Generation Internet (NGI) networks for experimental purposes are being built around the world. In addition, the IPv6 application is introduced to more and more countries as a respo…     

performance Evaluation of IPv4/IPv6 Networks for Ubiquitous Home-Care Service

Because of rapid development in network technology,Internet usage has become widespread.It allows users with sensing devices to obtain medical data for healthcare,such as physiological signals,voice,and video streams from telemedicine systems,and to send the healthcare data to back-end database systems,creating a ubiquitous healthcare environment.However,this environment requires a widespread and suitable network.IPv6(Internet protocol version 6) is the next-generation Internet protocol that will be the protocol of future networks;it improves many shortcomings of IPv4.In this paper,we propose an IPv6/IPv4 U-home-care test system and analyze the network’s parameters though a series of tests by adjusting network parameters to find the optimal design for applications in the IPv6/IPv4 U-home-care service so as to assure good performance and high quality.     

IPv4-IPv6 Multicast Transition Technologies

The need for IPv6 support for multicast has beenestablished for the next generation Internet and largemulticast address space is planned for this purpose.Though, the number ofIPv6 nodes increasing after itsimplementation, lots ofIPv4 nodes willstillremain for theirsuccess. Therefore, IPv6 won’t replace IPv4 in a short time, theywillco- exist for years. During that time an IPv6- only networkwillappear on a regional- basis according to IPv6 deploymentstrategy. In this case, pure IPv4 and…     

Next Generation Internet and IPv6 Transition

IPv4 address space has been exhausted since2011.The problem will be solved by moving forward to the next-generation Internet based on IPv6.Smooth transition from IPv4 to IPv6is the key to deciding whether the next-generation Internet is successful.IPv6-transition,hence,has been become the focus of both industry and academia.However,due to the staggering difficulty of IPv6-transition technology,most of the existing literatures merely describe the IPv6 specific protocol or conventional IPv6 transition technology,which     

A Novel Load Balancer for Scalable Multi-NAT

Due to the upcoming IPv4 address exhaus- tion, the transition from IPv4 to IPv6 becomes an urgent problem restricting the growth of Internet. Multi-NAT, which is desired in large scale IPv4-IPv6 coexistent net- work, has inherent difficulties in the stateful traffic bal- ancing and failure recovery. The existing schemes cannot handle them due to the absence of state synchronization. In this paper we propose a novel Load balancer （LB） to build a Scalable multi-NAT （SMNAT） in large scale net- work for various IPv4-IPv6 coexistent scenarios. The LB is specifically designed to have a translation pattern re- lated hash keys and load-balance bi-directional traffic in two modes. Additionally an Adaptive reassigning algo- rithm （ARA） running in LB is presented to schedule flows adaptively to reduce the cost of state synchronization as well as guarantee the performance in load balancing. Com- paring SMNAT with the existing load balancing schemes, the simulation result shows that our SMNAT outperforms other schemes and meets the goals of large scale NAT.     

Development of IPv6 Capabilities for Next Generation Internet

As more new machines are being added to the Internet, there is a growing shortage of IPv4 (IP Version 4) addresses. To save IPv4 addresses, technologies such as Network Address Translation (NAT), Classless Inter-Domain Routing (CIDR) and hybrid address are called into play. However, these emergency measures also bring forth negative effects. For example, the end-to-end architecture of the network layer is damaged. IPv6 (IP Version 6) fixes a number of problems in IPv4. The changes …     

非掺杂环栅MOSFETs的基于表面电势和非薄层电荷的核心模型

A surface potential based non-charge-sheet core model for cylindrical undoped surrounding-gate （SRG） MOSFETs is presented. It is based on the exact surface potential solution of Poisson＇s equation and Pao-Sah＇s dual integral without the charge-sheet approximation, allowing the SRG-MOSFET characteristics to be adequately described by a single set of the analytic drain current equation in terms of the surface potential evaluated at the source and drain ends. It is valid for all operation regions and traces the transition from the linear to saturation and from the sub-threshold to strong inversion region without fitting-parameters, and verified by the 3-D numerical simulation.     

A full W-band low noise amplifier module for millimeter-wave applications

A full W-band Low Noise Amplifier (LNA) Module is designed and fabricated in this letter. A broadband transition is introduced in this module. The proposed transition is designed, optimized based on the results from numerical simulations. The results show that 1 dB bandwidth of the transition ranges from 61 to 117 GHz. For the purpose of verification, two transitions in back-to-back connection are measured. The results show that transmission loss is only about 0.9-1.7dB. This transition is used to interface integrated circuits to waveguide components. The characteristic of the LNA module is measured after assembly. It exhibits a broad bandwidth of 75 to 110 GHz , has a small signal gain above 21 dB. The noise figure is lower than 5dB throughout the entire W-band (below 3 dB from 89 to 95GHz) at a room temperature. The proposed LNA module exhibits potential for millimeter wave applications due to its high small signal gain, low noise, and low dc power consumption     

IPv6过渡研究综述

IPv6已被确定为下一代互联网所使用的协议,现有网络向IPv6网络的过渡问题正成为研究热点.由于现有使用IPv4的互联网规模已经十分庞大,如何保护现有投资,使网络平稳过渡到IPv6是一个非常重要的问题.本文对IPv6过渡中的研究问题进行了综述,总结了IPv6过渡中使用的基本技术,对不同过渡场景下IPv6过渡技术的选择进行了比较和分析,对过渡中的安全问题进行了讨论.并分别从网络拓扑和协议层次角度对IPv6过渡进行了展望,指出了未来研究的方向.     

IPv4/IPv6过渡技术和方案分析

简要介绍了IPv4向IPv6过渡的主要技术,并针对我国IPv6发展情况对网络过渡方案进行了分析.     

未来移动通信的核心技术——IPv6

随着Internet数据业务和移动通信技术的迅速发展,基于Ipv4的Internet已不适应当前应用需求。Ipv6作为一种新型的Internet协议,克服了现有标准Ipv4在地址匮乏、路由表过于庞大和服务安全等方面的不足,Ipv6即将取代Ipv4成为下一代互联网的标准并且为未来移动通信提供重要支持。文中概括介绍了IPv6技术的特点和优势,如何实现IPv4到IPv6的过渡,并且讨论了IPv6对下一代移动通信的影响。     

IPv4／IPv6混合网络中的SIP通信解决方案

IPv6是IP协议的新版本,它最终会取代IPv4成为未来互联网的核心网络协议,然而,过渡时会有一段IPv4与IPv6共存时期。由IETF定义,SIP已成为多媒体通信的最重要技术之一。文中在分析SIP机制和常见的IPv4向IPv6过渡技术的基础上,提出了一种双协议栈与TURN相结合的解决方案。     

IPv4向IPv6过渡机制的研究

在IPv4向IPv6过渡时期,为保护现有投资,需要解决IPv4网络和IPv6网络之间的互联互通问题。介绍了三大类过渡技术的原理,详细分析了它们的工作机制和特点,并进行了综合评价,最后结合应用场合给出了各种技术的使用范围。     

IPv4/IPv6协议过渡机制的实验研究

从IPv4向IPv6的过渡是网络发展的一大趋势，但存在很多技术问题亟待解决。为了使这一过渡尽可能地平滑，人们提出了很多解决方法。本文研究了几种主流的过渡机制，并就一个基于隧道代理的过渡方案给出其具体实现方法，并进行了实验。实验证明，该方案有效地实现了对现有IPv4网络向IPv6的升级，并保证了IPv6网络与IPv4网络的互联互通。     

IPv4向IPv6过渡策略研究

为解决IPv4的设计缺陷,国际互联网工程任务组(IETF)开发了新一代Internet协议IPv6,但由于IPv4与IPv6之间存在着很大的差异,同时存在众多基于IPv4协议的网络及应用,因此,要用新的IPv6代替旧的IPv4只能采用逐步演进的办法,文章就现存的过渡策略做了研究和分析.     

IPv4/IPv6过渡的安全评估

近年来,由于Internet技术的迅猛发展,使得现在广泛使用的32位IP地址面临被用完的威胁,为此IETF 提出了下一代因特网协议(IPng)即IPv6,用来取代IPv4。本文介绍了IPv4/IPv6过渡技术的机制及过程,对各种IPV4/IPV6过渡技术的安全问题进行讨论,探讨了这些过渡机制安全方面的优劣、使用中的限制、应用方式及效果。     

面向IPv6的下一代互联网管理研究

大量基于IPv6的下一代互联网的部署对网络的管理提出了巨大的需求.由于IPv6地址结构、空间的巨大变化以及一些新的协议特性的引入,原有IPv4的管理方式已经无法对IPv6网络进行有效的管理,需要从体系结构和管理技术上进行新的研究.本文探讨了基于IPv6的下一代互联网管理面临的问题,综述了IPv6网络管理的研究进展,介绍了本课题组开发的一个IPv4/IPv6综合网络管理系统,并深入分析了过渡时期的网络管理问题.     

我国IPv6发展的整体目标和基础思路

我国发展IPv6将解决制约我国通信业发展的瓶颈,推动我国物联网和三网融合的步伐。但是,发展IPv6是一个演进过程,IPv4和IPv6将长期共存。首先提出我国发展IPv6可从网络边缘介入的基本策略,并描绘了发展IPv6分3阶段实施的整体目标。在分析从IPv4向IPv6演进的技术选项后,给出了我国发展IPv6的基础思路。