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随着对航空电信网(ATN)研究的深入,最初制定的OSI七层结构渐渐的表现出与航空发展要求的不相适应,表现最明显的是缺乏OoS服务。由于新一代IP技术(IPv6)能够很好的满足这些缺陷,因而,将IP移植进ATN在国际上达成了普遍共识。在IP QoS中,IETF提出了两种推荐结构:综合服务(IntServ)和区分服务(DiffServ)。通过分析,DiffServ更合适ATNQoS的要求,进而提出DiffServ ATN over DiffServ的模型,作为IPover ATN过渡阶段的实施方案。对IP和ATN数据包结构的分析可知两者在结构上的相似性,则通过映射的方法,证明DiffServ引入ATN可行。 相似文献
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吴志军 《中国民航学院学报》1997,15(6):26-37
基于航空电信网(ATN)、航空区域管制中心网络和航空机场多媒体信息显示技术上提出了一种可以提高现代化航空机场运营效率的新型航空机场综合、实时管理信息显示系统,大致介绍了其系统组成和主要功能,并对此信息显示系统的各个主要构成部分的设计实现及其之间的关系进行了描述。 相似文献
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基于对ATN与IP网络拥塞控制机制的比较,本文针对AT Nover IP方案提出了IP子网隧道中的明确拥塞通告(ECNT)模型,将明确拥塞通告(ECN)引入了AT Nover IP方案;还提出了ECNT模型中实现IP网络明确拥塞通告(ECN)与ATN网络传输层协议COTP中拥塞指示位(CE)的映射算法(ECN/CE),用以解决由于IP网络中TCP协议与ATN网络中COTP协议所采用的两种拥塞避免在机制上的差别而造成的拥塞信息跨网络传输的困难。仿真结果表明,与没有引入ECN的IP子网隧道模型相比,ECNT模型和ECN/CE算法可以解决IP网络为ATN的网络进行数据传输时的拥塞问题。 相似文献
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Network management is one of the most discussed topics in the networking fraternity. The efficiency of the network management suit is measured by the number of parameters/components handled by the application while making decisions. In the case of internet-enabled aircrafts, along with network security, even aircraft safety needs to be considered as a factor while designing the Network Management suit. This requires the Network Management suit to monitor/analyze the aircraft-related data (avionics data, physical security parameters, etc.) while determining the proper functioning of the overall system. Herein, these authors present a framework for Network Management suit that, along with network health, monitors inputs from avionics, video surveillance system, weather monitoring system, and manual pilot alarms, and based on the situation, reconfigures the on-board networking devices to stream appropriate flight-critical data to the ground station. The proposed framework attempts to provide a comprehensive user interface for the flight health monitoring crew with all relevant data. 相似文献
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传统的遥测体制已经不能满足日益增长的飞行试验需求,新型TmNS(Telemetry Network System,遥测网系统)需要RF(Radio Frequency,射频)网络管理来协调资源分配,以满足性能要求.首先介绍了TmNS的总体架构,其RF链路除传统下行遥测链路外,新增了一条双向数据链路,实现多个试验对象和多个地面站的组网.随后讨论了该网络系统RF链路管理的原理和流程.由于链路管理器根据网络容量来分配TxOp (Transmission Opportunity,传输机会),故重点研究和比较了2种动态容量分配算法——B-LM算法和E-LM算法,ELM算法较B-LM算法略复杂,但可以减小系统延时,二者可以在链路管理器中共存,依据网络情况进行配置或切换.最后简要分析了链路管理器的软件结构.RF网络管理是TmNS的一项关键技术,该研究将促进我国新一代遥测网的发展. 相似文献
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A preliminary analysis of the capacity (number of aircraft) that could be handled by the first generation American Mobile Satellite Corporation (AMSC) system in the early part of the 21st century is reported. The analysis is based on assumptions for the service demand, the Aeronautical Telecommunication Network (ATN), the communications scheme, the satellite channel and the aircraft Earth station. Capacity is examined in terms of spectral bandwidth required and satellite power limitations. The sensitivity of the results is examined with regard to variations in service demand; spectral efficiencies of different modulation techniques; aircraft antenna equipage, high-gain or low-gain; and the amount of overhead associated with the ATN. With regard to the ATN, the analysis only illustrates the impact on capacity if some of the ATN overhead were eliminated. The feasibility of eliminating this overhead and the possible resulting loss of functionality are not addressed 相似文献
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端到端虚拟组网系统解决企业内部网内信息终端用户之间的网络安全通信问题,实现了IPSec VPN系统及基于用户的工作组级安全策略管理系统。首先介绍了IPSec VPN协议与安全策略管理标准;然后对系统的总体框架进行了讨论与设计;在方案设计的基础上,详细论述了系统内的安全策略管理子系统与W indows端虚拟网子系统的实现,并对所使用的技术进行了说明;最后,介绍了系统的应用情况,并对系统下一步的工作目标进行了展望。 相似文献
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The Integrated Services Digital Network (ISDN) is currently evolving from its conceptualization by the CCITT international standards body to specification and implementation by network providers and equipment vendors. This paper provides an overview of ISDN standards that were approved by the CCITT in 1984, and identifies enhancements currently under study by the CCITT for 1988 approval. 相似文献
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The Federal Aviation Administration (FAA) currently has under development data link services for Air Traffic Management (ATM), Flight Information Service (FIS), and communications, navigation, and surveillance (CNS). These services will be provided over the Aeronautical Telecommunications Network (ATN), a worldwide data network intended to provide data communications connectivity among mobile aircraft, airlines, and civil aviation authorities. The ATM and FIS services currently under development are part of an evolutionary process that will begin, for the most part, with duplication of voice services. In the future, services will facilitate a common source of data for pilots, controllers, and flight planners, as well as computer-to-computer communications between ground based and airborne automation systems. These future services will provide benefits such as the use of optimum aircraft tracks and flight profiles 相似文献
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智能化建筑(小区)是一种崭新的人居环境,它给物业管理带来诸多不同以往的特点,尤其是在网络和设备管理方面。信息的流畅性与安全设施的完善使得物业管理工作较为舒适,网络设备功能的多样性使整体物业费用下降,但设备的先进性要求管理者具有较高素质。智能化网络与设备管理的核心工作是保持其长期、持续运行。这要求物业管理从以往的定性检查深入到对系统每个零部件物理层的定量化检测,保证网络与设备运行所需要的相关环境和条件,并对信息资源进行安全保护。 相似文献
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NASA's Glenn Research Center (GRC) is responsible for the Advanced Communications for Air Traffic Management (AC/ATM) Project, a sub-element task of the Advanced Air Transportation Technologies (AATT) Project of the NASA Airspace Systems Program. The AC/ATM Project is developing new communications technologies and tools that will enable Free Flight, an operating mode in which pilots will have the freedom to select their path and speed in real-time. The goal of the AC/ATM Project is to enable a communications infrastructure providing the capacity, efficiency, and flexibility necessary to realize benefits arising from the future mature Free Flight environment. A key infrastructure element is the Aeronautical Telecommunications Network (ATN) that the Federal Aviation Administration (FAA) is in the process of fielding. 相似文献
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自动测试标记语言(ATML)作为信息交换媒介可实现包括测试数据、测试资源数据、诊断数据和历史数据等信息共享。由ATML框架和组件标准组成的ATML系列标准为集成测试数据、测试策略和需求、测试步骤、测试结果管理和测试系统实现规定了整体系统环境。文章介绍了如何在某型装备远程测试维修系统中应用ATML来表示测试信息。自动测试标记语言将极大地促进自动测试技术的发展并具有广阔的应用前景。 相似文献
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《中国航空学报》2022,35(9):1-18
As an indispensable component of the emerging 6G networks, Space-Air-Ground Integrated Networks (SAGINs) are envisioned to provide ubiquitous network connectivity and services by integrating satellite networks, aerial networks, and terrestrial networks. In 6G SAGINs, a wide variety of network services with the features of diverse requirements, complex mobility, and multi-dimensional resources will pose great challenges to service provisioning, which urges the development of service-oriented SAGINs. In this paper, we conduct a comprehensive review of 6G SAGINs from a new perspective of service-oriented network. First, we present the requirements of service-oriented networks, and then propose a service-oriented SAGINs management architecture. Two categories of critical technologies are presented and discussed, i.e., heterogeneous resource orchestration technologies and the cloud-edge synergy technologies, which facilitate the interoperability of different network segments and cooperatively orchestrate heterogeneous resources across different domains, according to the service features and requirements. In addition, the potential future research directions are also presented and discussed. 相似文献
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认知无线网络通过不同种类的无线网络体系结构之间的并存和动态频谱接入技术可以为移动用户提供高带宽的服务。高效的频谱管理技术是这一新型网络面临的主要挑战之一。为了更好的理解认知无线网络,文章简单回顾了认知无线电技术,对认知无线网络的结构及特点进行了深入研究,明确了认知无线网络频谱管理的主要任务,并结合认知无线电当前的发展状况对认知无线网络频谱管理技术进行了总结分析。 相似文献
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Correctional Service Canada (CSC) has recently replaced the aging, out-of-date radio communications systems in all major CSC facilities with new conventional digital radio systems. Based on very specific and restrictive operational requirements coupled with developments in digital radio technology and the Associated Public Communications Officers (APCO) Project 25 digital radio standards, it was determined that digital radio communications would best meet CSC's needs. The CSC national radio replacement program was completed in March 2000. Switching to a digital radio communications system gave CSC an opportunity to consider changing the existing radio system from a number of conventional, single-site systems to a trunking system. Areas to be considered when determining the architecture for a radio communication network, whether radio trunking systems or conventional radio systems should be used, are presented, In addition, the paper will also outline the requirements and measures taken to keep the radio communication network active and operational while the equipment was converted from an analog technology to a digital one 相似文献
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应急通信网络必须能在紧急突发事件发生时利用多种通信技术手段快速、有效为不同用户群体提供可靠、灵活的通信服务.首先介绍了构建一体化应急通信网络的背景,然后说明了应急通信网络的构建要求.在此基础上,详细阐述了一体化应急通信网络体系框架的构想方案,并探讨了实现这种网络涉及的无线自组网、移动切换和QoS支持等关键技术问题. 相似文献