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1.
介绍了下一代网络NGN的概念、基本特征;对基于目前互联网的IPv4协议和NGN的支撑技术IPv6进行了对比;分析了从IPv4到IPv6的几种过渡技术,最后探讨了NGN和IPv6的关系,提出了目前NGN和IPv6要解决的一些问题。 相似文献
2.
由于IPv4存在的不足,IPv6协议自然成为下一代互联网的核心技术。文章根据IPv6的优良特点,指出应尽快建设基于IPv6的高校图书馆网络或对目前IPv4的网络进行升级,这将给高校图书馆的网络建设带来许多新应用。同时,对IPv6的过度技术进行分析,简要论述了高校图书馆IPv6网络建设过程中应注意的原则和实施方案。 相似文献
3.
下一代校园网IPv6网络的构建与分析 总被引：1，自引：0，他引：1
IPv6作为下一代互联网的核心协议,能提供高效、安全、可靠和优质的服务。文章在比较IPv4与IPv6网络的差异后,介绍了IPv4向IPv6网络过渡的策略,以及校园网实施过渡的指导原则,最后对IPv6网络的安全进行了简单的阐述。 相似文献
4.
众所周知,IPv6是下一代互联网的主要协议,它虽具有许多优越性,却也有不足.本文简要介绍了IPv6协议的优势.探讨了JPv6网络的安全特性,分析并研究了未来IPv6网络面临的一系列安全问题. 相似文献
5.
近些年来,人们对于互联网的需求越来越多,间接推动了IPv6的快速发展,IPv6已经逐渐取代了IPv4,被广泛应用与互联网中,不仅要保证业务之间的连贯性,还要确保绝对的安全性。然而,目前IPv6中仍旧存在很多的安全隐患,这样问题很可能会造成用户数据的丢失,甚至被盗窃,严重影响了IPv6的快速发展。因此,本文针对IPv6的下一代网络技术与网络安全进行深入的研究探讨,对IPv6本身存在的安全弊端做出分析,提出相关有效的解决办法。 相似文献
6.
随着网络技术的发展,网络理论也面临着新的挑战。主要分析了网络理论在基于IPv6下一代网络技术中的新发展,以期对网络教育的发展有所启迪。 相似文献
7.
IPv6校园网的建设是中国下一代互联网(CNGI)的重要组成部分,它是在IPv4校园网络的基础上进行的新的建设。因此,IPv6校园网的规划、配置和建设方案就需要依据不同高校的网络状况和不同的实现技术进行设计。 相似文献
8.
IPv6以其丰富的IP地址资源、安全性、网络管理、服务质量等方面的优势,必将成为替代IPV4的新一代网际协议。由于IPv6协议不能完全兼容IPv4协议,因此IPv4协议向IPv6协议过渡的过程,将利用现有IPv4互连网络资源,采取逐步过渡的方式进行,CNGI网络（即下一代互联网）作为采用IPV6协议的下一代互联网将在较长的一段时间内与目前的IPV4网络共存。 相似文献
9.
IPv6是“Internet Protocol Version 6”的缩写,也被称作下一代互联网协议,它是由IETF（The Internet Engineering Task Force）设计的用来替代现行的IPv4协议的一种新的IP协议。IPv6内置IPSec协议,为网络安全问题提供了一种标准的解决方案,本文介绍了基于IPv6的下一代计算机网络的安全性问题,对IPSec的工作原理进行了分析,并提出了改进意见。 相似文献
10.
IPv6是"Internet Protocol Version 6"的缩写,也被称作下一代互联网协议,它是由IETF(The Internet Engineering Task Force)设计的用来替代现行的IPv4协议的一种新的IP协议。IPv6内置IPSec协议,为网络安全问题提供了一种标准的解决方案,本文介绍了基于IPv6的下一代计算机网络的安全性问题,对IPSec的工作原理进行了分析,并提出了改进意见。 相似文献
11.
A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
12.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
13.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
14.
Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
15.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
16.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
17.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
18.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
19.
Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
20.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献