THE DEVELOPMENT OF AERONAUTICAL SATELLITE COMMUNICATIONS (Ⅰ)

This paper presents an overview of the development of aeronautical satellite communi-cations over the past 30 years. The initial development of aeronautical satellite communications is de-scribed in the paper. The civil aviation growth and current unaccommodated communication systemsare discussed as well. The inherent shortcomings of present air-ground HF communications have hin-dered the development of civil aviation. but according to the Future Air Navigation Systems(FANS) concept aeronautical satellite communication-including Automatic Dependent Surveillance(ADS)-will be the key to eliminating the shortcomings of HF communication systems. Satellite-basedcommunication and surveillance will significantly improve air traffic control (ATC) over the oceanicand remote terrestrial airspace, and it will benefit civil aviation authorities, airlines as wel as passen-gers. This paper discusses the availability of system elements, and world wide trials, demonstrtionsand preoperational use of aeronautical satelli     

融合网络中民航通信安全探索

ATN民航通信网是一个融合网络,在协议、报文格式、通信模式上异于互联网,可能遭受的攻击路径和方法也不同。研究甚高频数据链通信安全问题,有助于提高民航交通通信安全应急响应能力。     

民航空管通信网可靠性初探

文章对空管通信系统运行中影响其可靠性的因素进行了分析,从空管通信网特性角度出发,有针对性的提出了空管通信系统可靠性研究的思路和方法。同时,以民航通信网为例,对通信网备份系统的构造、评价方法步骤和可靠性管理思路进行了探讨。     

利用ATM技术建设的民航通信网络

目前,民航空管系统的通信网络主要是由平面通信网和地空通信网这两个互相独立的网络组成。文章以民航ATM网为主干,讨论了民航空管系统通信网络建设的发展方向即民航平面通信网和地空通信网互连、互通的可能性以及在技术上所遇到的挑战。展望了语音、数据、视频3网合1在民航通信网中的发展前景。     

基于虚拟化技术的空管数据中心构架研究

Based on the analysis of the current situation of the informatization construction of civil aviation air traffic control indus- try, combined with the personnel qualification, hardware resource utilization, data integrity analysis and data security problems in the field of air traffic control industry, this paper puts forward a data center construction framework based on VMware virtual cloud platform. This paper studies on the revolutionary change of the traditional data center brought by the virtualization technology of VMware, and gives a specific case analysis for the application of its advantages in the air traffic control, especially for the special non-stop air traffic control construction situation. The high availability migration of VMware can effectively improve the resource utilization and security guarantee of the data center, and effectively improve the air traffic control's Safe operation level.     

Advances in vehicular ad-hoc networks (VANETs): Challenges and road-map for future development

Recent advances in wireless communication technologies and auto-mobile industry have triggered a significant research interest in the field of vehicular ad-hoc networks (VANETs) over the past few years. A vehicular network consists of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications supported by wireless access technologies such as IEEE 802.11p. This innovation in wireless communication has been envisaged to improve road safety and motor traffic efficiency in near future through the development of intelligent transportation system (ITS). Hence, governments, auto-mobile industries and academia are heavily partnering through several ongoing research projects to establish standards for VANETs. The typical set of VANET application areas, such as vehicle collision warning and traffic information dissemination have made VANET an interesting field of mobile wireless communication. This paper provides an overview on current research state, challenges, potentials of VANETs as well as the ways forward to achieving the long awaited ITS.     

超高速移动空 空宽带通信网及其物理层关键技术

随着航空事业的迅速发 展和空中通信终端的日益增加,构建支持超高速移动的空中宽带通信网络已成为未来航空通 信和军事通信发展的迫切需求。本文首先简要概述航空通信网络现状和发展趋势,在此基础 上指出实现超高速移动空 空宽带通信网络所面临的支持超高速移动、支持高数据传输速率 、支持远距离单跳链接、支持大规模自组网和多用户访问机制等挑战性问题,并分析其相互 制约关系。最后重点讨论空 空宽带通信网物理层关键技术及其研究现状,包括调制技术、 正交频分复用的峰均功率比抑制、频偏估计、信道估计与信道建模等。     

A generalized higher order neural network for aircraft recognition in a video docking system

In modern world of today where air traffic is continuously increasing and available space at the airports remains finite, there is a problem of safe docking of aircraft. The problem needs to be solved to ensure safe and smooth movement of aircraft, passengers and crew while making optimum utilization of available ground space. Without such systems having in place, accidents keep occurring due to human judgment errors. These accidents are causing loss of material costs and human injury. The importance of Video-based Docking Systems is continuously increasing due to the challenges of current and upcoming traffic demands of future. This paper evaluates two neural networks architectures for recognition of civil airliners in a Video docking system. The networks compared are feedforward neural network and probabilistic neural network. The results are compared by presenting data to neural networks while deforming the shape, adding noise and partly occluding the shape and presenting those angles for which network was not trained.     

国家航空电信网的建设研究

航空电信网是CNS/ATM系统的重要组成部分,是下一代航空通信系统的全面解决方案.建立一个全球化的、开放结构的互联网络,使空中交通管制系统、航空公司、航空行政管理部门的各种网络有机地连接成一个整体,达到系统互联、信息互通、资源共享的目标是目前研究的热点问题.通过对航空电信网的基本概念、网络组成、协议结构等特点的阐述,分析了当前航空电信网研究中存在的关键问题.结合现行空中管制体制建设的特点,对航空电信网建设提出建议.     

基于KDC的无线工业控制网络安全研究

无线通信在工业现场中的使用日益广泛,给无线工业控制网络带来了新的安全问题和挑战。面对无线工业控制网络的新形势,文中探讨了无线工业控制网络的安全风险。针对目前无线工控接人认证缺失的脆弱性,在分析无线工业控制网络的层次级安全架构的基础上,提出了一种适用于该架构的通信双方安全认证方案,构建基于密钥分配中心（KeyDisstibutionCenter,KDC）的无线工业控制网络密钥管理方法,保证无线工业控制网络通信双方的身份安全。     

基于系统最优的航空信息网络流量均衡方案

随着未来空战的需求,当前的航空信息网络逐渐暴露出种种不足,如针对不同作战任务网络应具备较强的差异化服务能力、网络中各平台节点间的信息不能得到及时共享、网络规模的增加导致网络中流量发生拥塞和网络架构更加臃肿等问题,而SDN的出现较好地解决了这一问题,通过将SDN与航空信息网络相结合,创新性地提出了一种软件定义航空信息网络。文中面向航空信息网络中的流量传输问题,针对网络中流量分布不均衡的情况,提出了一种基于系统最优(System Optiminzation,SO)的流量负载均衡方案。文中通过构建混合SDN/IP航空信息网络模型,在网络中利用SDN控制器的集中控制特性使SDN节点对业务流量进行多路径转发,进而实现对其调度优化,并定义链路拥塞系数和SDN数据流,以链路利用率最小为目标,利用Wardrop均衡理论分析求解,参照系统最优原则,并提出一种基于SO的流量均衡分配算法。为体现所提算法的优越性,仿真中同时设置了SMR算法和MSR算法,结果表明SOA算法在业务完成率与业务吞吐量方面均有显著提升,如在大规模网络中,MSR和SMR算法的业务完成率分别为58.4%和52.2%,而SOA算法的业务完成率大约为70.5%,性能分别提升了20.7%和35.1%,因此所提算法对网络中流量的转发实现了较好的处理,为解决未来航空信息网络下的流量传输问题提供了一种新思路。     

A Secure Correspondent Router Protocol for NEMO Route Optimization

The Network Mobility (NEMO) protocol is needed to support the world-wide mobility of aircraft mobile networks across different access networks in the future IPv6 based aeronautical telecommunications network (ATN). NEMO suffers from the constraint that all traffic has to be routed via the home agent though. The already existing correspondent router (CR) protocol solves this triangular routing problem and permits to route packets on a direct path between the mobile network and the ground based correspondent nodes. We identify security deficiencies of this protocol that make it unsuitable for use within the ATN. We therefore propose a new route optimization procedure based on the CR protocol that provides a higher level of security. We evaluate our new protocol in three ways. We first conduct a simulation based handover performance study using an implementation of a realistic aeronautical access technology. We then investigate the mobility signaling overhead. Finally, we specify a threat model applicable for the aeronautical environment and use it to perform a security analysis of both the old and our new protocol. It is shown that our protocol is not only more secure but also provides better handover latency, smaller overhead in the aeronautical scenario and a higher level of resilience when compared to the original CR protocol.     

Performance evaluation of network mobility handover over future aeronautical data link

The aviation community is currently working on the standardization of data communication systems for the future air traffic management. In this context, International Civil Aviation Organization (ICAO) has initiated a work on standardization of an IPv6-based aeronautical telecommunications network and on future radio access technologies, respectively. In this paper, we integrate L-Band Digital Aeronautical Communications System Option 1 (L-DACS 1), which is one candidate for future radio access technologies, with realistic IPv6-based network layer functionality and analyze the effect of handover delay to the TCP performance. Realistic Frame Error Rate (FER) values obtained from an L-DACS 1 physical layer simulator, which uses a realistic aeronautical channel model, are used in the simulation experiments. In the first stage, we decreased layer 3 handover latency by removing the Duplicate Address Detection (DAD) procedure for address configuration. In the second stage, we introduced a Home Agent (HA)-buffering method, which is used to buffer the traffic (destined to the mobile node) during handover. Transmission completion time is the primary performance metric in our analysis. With the HA-buffering method, the transmission completion time is reduced by at least 10% for the transmission of 110 kB of information over a wireless link with 31.5 kbit s⁻¹ data rate.     

5G网络在智能交通中的应用发展趋势分析

Along with the advent of 5G era, China's transportation industry for intelligent development enters into the fast lane. Based on the integration of communication technology, Internet of things technology, big data technology, cloud computing technology, ar- tificial intelligence technology and so on, the whole process and all-round intelligent control are carried out in traffic construction, traffic management, road transportation, traffic service and so on, so as to ensure smooth and safe travel and to provide good servic- es to road, railway, civil aviation, water transportation and other transportation networks. It is the important feature of intelligent transportation in the 5G era. This paper analyses the trend of application and development of 5G network in intelligent transporta- tion, which is the research basis of perfecting transportation service and the scientific basis of promoting the intelligent and modern development of transportation in China.     

浅析通信网络优化与安全

随着计算机和通信技术的迅速发展,通信网络获得了广泛应用和飞速发展,对于提高通信的有效性起到了重要作用。然而,在通信网络的发展过程中依然存在着一些问题,因此,如何做好通信网络的优化工作,提高通信安全,成为通信行业普遍关注的问题。本文主要分析了通信网络优化的必要性和加强通信网络优化和安全的具体措施。     

Fostering civil associations in Africa through Governet: An administrative reform network

Abstract

The use of electronic communications technology in the developing world context brings forth challenges that may potentially unleash the power of civil society by fostering networking among civil servants involved in public administration reform. This paper highlights the key considerations that drive the need for building civil associations through networks and explores the development of GOVERNET, an administrative reform network and concludes with some insight into the salient issues driving this form of networking.     

民航气象传真广播系统通信机制分析

在民航改造的气象传真广播系统（简称621系统）中,通信分系统是最重要也是最复杂的分系统。该文对民航气象传真广播系统的通信机制进行了详细的分析,主要阐述了气象传真广播系统中通信分系统的整体架构,通信服务器业务处理流程和各通信进程之间的相互关系,预报平台所发数据的处理流程,以及数据库服务器接收数据流程。可作为今后日常维护和管理整个系统的有益参考。     

网络通讯安全与防护措施

随着计算机技术和网络通讯技术的普及应用,计算机网络已经逐渐成为人们日常工作与生活必不可缺的重要内容。网络通讯技术再给人们带来便利,提高人们生活效率的同时,也带来了一些问题,现阶段网络通讯安全已经成为一个较为突出的社会问题之一。本文将重点探讨网络通讯安全与防护措施的相关内容,为提升网络通讯应用水平提供参考。     

第二代洋葱头路由匿名通信系统-Tor

Tor网络是目前Internet中最成功的公共匿名通信服务。首先简要概述了匿名通信和Tor网络的基本原理洋葱头路由。然后从三个方面对Tor网络进行了详细的阐述,具体为:Tor协议阐述了Tor的传输单元、通道构建机制和应有数据流传输机制;Tor网络的现状阐述了Tor网络目前的状态,包括用户和节点的分布情况,使用Tor网络服务的应用层协议情况和Tor网络的滥用情况;Tor未来发展面临的挑战,包括系统可用性的挑战、系统信誉度的挑战和系统抗滥用能力的挑战。     

AOM: adaptive mobile data traffic offloading for M2M networks

With the increasing application of machine-to machine (M2M) communication through cellular networks, such as telematics, smart metering, point-of-sale terminals, and home security, more data traffice has been produced in the cellular network. Although many schemes have been proposed to reduce data traffic, they are inefficient in practical application due to poor adaption. In this paper, we focus on how to adaptively offload data traffic for cellular M2M networks. To this end, we propose an adaptive mobile data traffic offloading model (AOM). This model can decide whether to adopt opportunistic communications or communicate via cellular networks adaptively. In the AOM, we introduce traffic offloading rate (called TOR) and local resource consumption rate (called LRCR) and analyze them based on continue time Markov chain. Theory proof and extensive simulations demonstrate that our model is accurate and effective, and can adaptively offload data traffic of cellular M2M networks.