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991.
992.
随着流媒体、视频等业务在Internet上的相继开展,IP组播技术和应用开始快速发展。本文主要分析IP组播技术的产生、概念和特点,以及相关技术,结合油田开发实际, 介绍了IP组播技术在油田开发监控中的应用。 相似文献
993.
We present a BIST architecture based on a Multi-Input Signature Register (MISR) expanding single input vectors into sequences, which are used for testing of delay faults. Input vectors can be stored on-chip or in the ATE; in the latter case, a low speed tester can be employed though the sequences are applied at-speed to the block-under-test. The number of input vectors (and thus the area demand on-chip or ATE memory requirements) can be traded for the test application time.We propose several methods for generating input vectors, which differ in test application time, area requirements and algorithm run-time. As all of them require only a two-pattern test as input, IP cores can be handled by these methods.The block-under-test can be switched off for some amount of time between application of consecutive input vectors. We provide arguments why this approach may be the only way to meet thermal and power constraints. Furthermore, we demonstrate how the BIST scheme can use these cool-down breaks for re-configuration. 相似文献
994.
Micromobility protocols such as Cellular IP, Hawaii and Hierarchical Mobile IP are developed to solve problems of high handoff
latency and control overhead, which occur when Mobile IP is used in combination with frequent handoffs. Up to now, tree access
network topologies are considered to evaluate the protocol performance. However, for reasons of robustness against link failures
and load balancing, extra uplinks and mesh links in the topology are desired. This article makes a classification of several
topology types and gives a model that points out to which extent the topology influences the protocol performance in terms
of handoff latency and handoff packet loss. Simulations confirm the results calculated by the model. Performance metrics such
as load balancing, end-to-end delay and robustness against link failures are also evaluated. The study points to several shortcomings
of the existing micromobility protocols for different topology types. Several aspects of the studied handoff schemes, their
advantages and drawbacks are identified.
L. Peters is a Research Assistant of the Fund for Scientific Research – Flanders (F.W.O.-V., Belgium)
Liesbeth Peters was born in Temse, Belgium, in 1978. She received her Master of Science degree in Electrotechnical Engineering from Ghent
University, Gent, Belgium in 2001. Since August 2001, she has been working as a doctoral researcher with the Department of
Information Technology (INTEC) of the Faculty of Applied Sciences, Ghent University, where she joined the Broadband Communications
Networks Group. Since October 2002, she works there as a research assistant of the Fund for Scientific Research—Flanders (F.W.O.-V.,
Belgium). Her current research interests are in broadband wireless communication and the support of IP mobility in wired cum
wireless networks.
Ingrid Moerman was born in Gent, Belgium, in 1965. She received the degree in Electro-technical Engineering and the Ph.D degree from the
Ghent University, Gent, Belgium in 1987 and 1992, respectively. Since 1987, she has been with the Interuniversity Micro-Electronics
Centre (IMEC) at the Department of Information Technology (INTEC) of the Ghent University, where she conducted research in
the field of optoelectronics. In 1997, she became a permanent member of the Research Staff at IMEC. Since 2000 she is part-time
professor at the Ghent University. Since 2001 she has switched her research domain to broadband communication networks. She
is currently involved in the research and education on broadband mobile & wireless communication networks and on multimedia
over IP. Her main research interests related to mobile & wireless communication networks are: adaptive QoS routing in wireless
ad hoc networks, personal networks, body area networks, wireless access to vehicles (high bandwidth & driving speed), protocol
boosting on wireless links, design of fixed access/metro part, traffic engineering and QoS support in the wireless access
network. Ingrid Moerman is author or co-author of more than 300 publications in the field of optoelectronics and communication
networks.
Bart Dhoedt received a degree in Engineering from the Ghent University in 1990. In September 1990, he joined the Department of Information
Technology of the Faculty of Applied Sciences, University of Ghent. His research, addressing the use of micro-optics to realize
parallel free space optical interconnects, resulted in a PhD degree in 1995. After a 2 year post-doc in opto-electronics,
he became professor at the Faculty of Applied Sciences, Department of Information Technology. Since then, he is responsible
for several courses on algorithms, programming and software development. His research interests are software engineering and
mobile & wireless communications. Bart Dhoedt is author or co-author of more than 100 papers published in international journals
or in the proceedings of international conferences. His current research addresses software technologies for communication
networks, peer-to-peer networks, mobile networks and active networks.
Piet Demeester finished his PhD thesis at the Department of Information Technology (INTEC) at the Ghent University in 1988. At the same
department he became group leader of the activities on Metal Organic Vapour Phase Epitaxial growth for optoelectronic components.
In 1992 he started a new research group on Broadband Communication Networks. The research in this field resulted in already
more than 300 publications. In this research domain he was and is a member of several programme committees of international
conferences, such as: ICCCN, the International Conference on Telecommunication Systems, OFC, ICC, and ECOC. He was Chairman
of DRCN’98. In 2001 he was chairman of the Technical Programme Committee ECOC’01. He was Guest Editor of three special issues
of the IEEE Communications Magazine. He is also a member of the Editorial Board of the Journals “Optical Networks Magazine”
and “Photonic Network Communications”. He was a member of several national and international PhD thesis commissions. Piet
Demeester is a member of IEEE (Senior Member), ACM and KVIV. His current research interests include: multilayer networks,
Quality of Service (QoS) in IP-networks, mobile networks, access networks, grid computing, distributed software, network and
service management and applications (supported by FWO-Vlaanderen, the BOF of the Ghent University, the IWT and the European
Commission). Piet Demeester is currently full-time professor at the Ghent University, where he is teaching courses in Communication
Networks. He has also been teaching in different international courses. 相似文献
995.
目前,单片机的嵌入式系统资源有限、性价比低、灵活性差,很难实时地并行运行复杂的网络通信协议和数字信号的编解码算法。把并行处理技术应用于嵌入式网络系统.协议和算法由不同处理器完成,真正提高了系统的处理能力和运算速度。通过设计并实现了一个基于并行处理的语音网络终端平台,验证了本研究方法的科学性和可行性。 相似文献
996.
本文分析了在PSTN中引入IP中继传输的基本需求,给出了承载信道IP中继传输的协议设计,并针对IP中继传输的效益性能做了简要的计算分析。结果表明,在典型话务量负载下,通过IP中继传输,带宽利用率能降至约13%。 相似文献
997.
998.
999.
IP网络路由容错是指网络在一个路由器发生故障不能工作时,另一个路由器自动接管失效的路由器,从而保证网络路由正常进行.介绍一种基于Cisco路由器的路由容错方法. 相似文献
1000.
王炜 《石油工业计算机应用》2007,15(3):10-12
虚拟专用网(VPN)代表了当今网络发展的最新趋势,它综合了传统数据网络的性能优点(安全和QoS)和共享数据网络结构的优点(简单和低成本),并能够提供远程访问外部网和内部网的连接。目前VPN主要采用四项技术来保证安全,这四项技术分别是隧道技术(Tunneling)、加解密技术、密钥管理技术、使用者与设备身份认证技术。本文将重点介绍如何选择合适的隧道技术来实现陆梁自动化远程监控系统。 相似文献