下一代异构IP网络的关键技术

异构无线网络融合是移动通信系统发展的重要趋势，即融合的网络将统一于全IP。不同网络的实现技术、传输机理、组织方式、控制机制存在巨大差异，这对异构网络中诸如移动性管理、联合无线资源管理、端到端的QoS保证等关键问题提出了极大的挑战。文章就异构网络的关键技术发展进行了分析和讨论。     

一种新型IP数据链网络路由算法模型

针对无线数据链网络,提出了一种新型的基于分层结构的IP路由算法模型,满足至少3种异构数据链网络的集成要求.仿真结果表明,该模型可有效支撑基于链路带宽、传输时延、链路质量等多种QoS的路由算法设计,为无线数据链网络层IP路由协议和算法设计提供了理论框架和实现指导.     

下一代异构IP网络的关键技术

异构无线网络融合是移动通信系统发展的重要趋势,即融合的网络将统一于全IP。不同网络的实现技术、传输机理、组织方式、控制机制存在巨大差异,这对异构网络中诸如移动性管理、联合无线资源管理、端到端的QoS保证等关键问题提出了极大的挑战。文章就异构网络的关键技术发展进行了分析和讨论。     

下一代异构IP网络的关键技术

异构无线网络融合是移动通信系统发展的重要趋势,即融合的网络将统一于全IP.不同网络的实现技术、传输机理、组织方式、控制机制存在巨大差异,这对异构网络中诸如移动性管理、联合无线资源管理、端到端的QoS保证等关键问题提出了极大的挑战.文章就异构网络的关键技术发展进行了分析和讨论.     

战术异构网络互联端到端QoS研究

战术异构通信网络的融合,需要更完善的端到端服务质量（Quality of Service,QoS）体系。在研究和分析战术异构通信网特点后,分析总结出战术异构通信网络端到端QoS研究内容,并参考下一代网络QoS框架结构,提出了基于策略的QoS架构模型。最后阐述了所涉及的关键技术,用于解决在战术异构通信网中不同业务在跨网络传输时端到端QoS保证,合理利用无线网络资源,有效提高数据传输性能等问题。     

QualNet环境下数据链的性能仿真

战术数据链是数据通信技术在军事方面的典型应用,主要采用通信网络技术和应用协议,实现机载、陆基和舰载战术数据系统之间的新型数据交换及战术系统的各项功能,因此组网协议的研究是数据链系统工作的核心.文中介绍QualNet环境下数据链的系统建模和系统仿真实验,得到数据链的网络规模、网络循环周期、系统响应时间、MAC端到端时延等总体性能指标,以及这些总体性能的影响因素和相互关系.     

一种低开销的数据链网络动态路由协议

针对现有无线自组织网络路由协议路由开销大或者时延长,不适合直接应用于数据链网络的问题,本文提出一种低开销的数据链网络动态路由协议。通过将路由消息嵌入数据链网络运行本身发送的消息中,以较小的网络开销为数据链网络成员提供实时动态的路由服务。实验结果验证了路由协议的有效性。     

一种基于卫星IP网络的数据链路层协议

通过分析卫星通信网络发展趋势,阐述卫星网络中现有的数据链路层协议,梳理归纳卫星网络的特点及影响,提出了一种新型卫星网络数据链路层协议(New Satellite Link Protocol,NSLP)。分析对比表明,该协议能够有效降低链路层报头开销,提高信息传输效率。在实际应用中,新型协议具有能够简化数据链路层的功能,有与TCP/IP协议兼容性好、与IP协议耦合度高、节约星上资源等诸多优点,有利于卫星IP网络整体性能的有效提升。     

基于战术互联子网的路由协议性能仿真比较

本文对基于移动Ad Hoc网络的营连以下战术互联子网的网络环境以及应用业务类型特点进行了分析,通过OPNET仿真软件对AODV、DSR和OLSR路由协议在CBR、FrP和Voice三种不同业务类型下进行了仿真,分析了路由协议的平均端到端延时、平均吞吐量和路由控制开销.仿真结果表明,在营连以下战术互联子网在进行战场态势感知任务时,AODV和OLSR协议性能较好;而进行语音话务任务时,OLSR比其AODV和DSR协议性能好.     

多源融合的数据链网络性能评估方法研究

针对无线通信条件下数据链网络性能测试和评估难题,设计了数据链网络性能评估方法。首先,采集数据链的记录数据;然后,通过对战术数据系统(Tactical Data System, TDS)数据的消息协议解析,按照数据链消息标准格式化TDS数据,提取时间、消息类型、数据链平台和收发消息四维变量;最后,结合集合映射理论,分析通信网络连通性,生成连通性评估报告和战术消息时序图。基于数据链网络实际业务数据,分析了测试样本经过传输造成的丢包、误码和时延抖动等影响,验证了多源融合方法的可行性和有效性。     

PACMAN: passive autoconfiguration for mobile ad hoc networks

Mobile ad hoc networks (MANETs) enable the communication between mobile nodes via multihop wireless routes without depending on a communication infrastructure. In contrast to infrastructure-based networks, MANET's support autonomous and spontaneous networking and, thus, should be capable of self-organization and -configuration. This paper presents passive autoconfiguration for mobile ad hoc network (PACMAN), a novel approach for the efficient distributed address autoconfiguration of mobile ad hoc networks. Special features of PACMAN are the support for frequent network partitioning and merging, and very low protocol overhead. This is accomplished by using cross-layer information derived from ongoing routing protocol traffic, e.g., address conflicts are detected in a passive manner based on anomalies in routing protocol traffic. Furthermore, PACMAN assigns Internet protocol (IP) addresses in a way that enables their compression, which can significantly reduce the routing protocol overhead. The performance of PACMAN is analyzed in detail based on various simulation results.     

美国空军短波全球通信系统技术分析

短波全球通信系统HFGCS,是高度自动化短波通信系统,为美国空军全球作战飞机部署和战略任务提供通信链路。这里首先介绍了HFGCS基本情况,然后分析了IP路由、短波台站控制信令和通信数据IP承载、短波无线IP协议、短波端到端保密互通等HFGCS具有特点的技术,最后给出了对中国短波通信网络发展的启示,建议加强短波台站收发信台资源统一调度、短波通信无线IP协议、短波通信信息分发、短波端到端保密通信等技术应用研究,各个层次都使用IP技术体制,保持短波通信网发展的可持续性。     

Intelligent Handoff for Mobile Wireless Internet

This paper presents an intelligent mobility management scheme for Mobile Wireless InterNet – MWIN. MWIN is a wireless service networks wherein its core network consisting of Internet routers and its access network can be built from any Internet-capable radio network. Two major standards are currently available for MWIN, i.e., the mobile IP and wireless LAN. Mobile IP solves address mobility problem with the Internet protocol while wireless LAN provides a wireless Internet access in the local area. However, both schemes solve problems independently at different layers, thereby some additional problems occur, e.g., delayed handoff, packet loss, and inefficient routing. This paper identifies these new problems and performs analyses and some real measurements on the handoff within MWIN. Then, a new handoff architecture that extends the features of both mobile IP and wireless LAN handoff mechanism was proposed. This new architecture consists of mobile IP extensions and a modified wireless LAN handoff algorithm. The effect of this enhancement provides a linkage between different layers for preventing packet loss and reducing handoff latency. Finally, some optimization issues regarding network planning and routing are addressed.     

战术互联网中的OLSR路由协议研究

战术互联网是无线移动环境下的战术通信骨干网络,是实现战场前沿态势感知数据和指挥控制数据传输的主要通道.OLSR(Optimized Link State Routing Protocol)是一种适合在移动Ad Hoc网中使用的路由协议,它采用了MPR (MultiPoint Relay:多点中继)机制以减少控制开销.文中以战术互联网系统为背景,结合其应用要求,对OLSR路由协议进行了算法和仿真研究,得到了有用的结果.     

A lightweight stateful address autoconfiguration for 6LoWPAN

Sensor networks have become increasingly important in various areas, and most current applications require connectivity between sensor networks and the Internet. By being seamlessly integrated into IP network infrastructure, sensor network applications would benefit from standardized and established technology, as well as from the plethora of readily available applications. Preparing sensor networks for IP communication and integrating them into the IP network, however, present new challenges on the architecture and its functional blocks, e.g., the adaptation of the respective link technology for IP support, development of security mechanisms, and autoconfiguration to support ad hoc deployment. In this paper, we focus on the IPv6 address autoconfiguration issue and propose a proxy-based autoconfiguration protocol. The proposed protocol guarantees the assignment of a unique address to each node in the network. The protocol is simulated and implemented on off-the-shelf sensor network platforms. The experiment results show that our mechanism outperforms similar network address configuring mechanisms in terms of latency and overhead.     

IDSDDIP: a secure distributed dynamic IP configuration scheme for mobile ad hoc networks

In IP‐based networks, IP address uniqueness is one of the most important requirements since a node has to participate in unicast communications and routing. Often nodes are assumed to have unique IP addresses configured a priori. However, this is not the case and cannot be achieved easily in mobile ad hoc networks (MANETs). Most of the existing dynamic address allocation schemes of MANET rely on network‐wide flooding for address solicitation and/or duplicate address detection. As a result, several types of security threats can be seen at the time of address allocation. In this paper, we present an ID‐based distributed dynamic IP configuration scheme that securely allocates IP addresses to the authorized nodes without flooding the entire network. Here each node acquires capability of generating unique IP addresses from its own IP address and can assign those addresses to the new nodes. The proposed scheme provides security against the associated threats with dynamic IP allocation protocol without the help of a trusted third party. It also efficiently handles the network partitioning and merging and reduces the chance of address conflicts. Performance analysis and simulation results are present to show that the proposed addressing scheme has low communication overhead and fairly low addressing latency with added security mechanisms compared to the similar existing dynamic address allocation schemes. Copyright © 2013 John Wiley & Sons, Ltd.     

Dynamic Adaptive Routing for a Heterogeneous Wireless Network

This paper presents an integrated architecture of a Heterogeneous Wireless Network (HWN) and a dynamic adaptive routing protocol (DARP) for a HWN. To allow mobile users versatile communication with anyone or any device at any place and anytime, HWN integrates cellular network with an ad hoc network (independent Basic Service Set) in wireless local area network (WLAN) and reserves advantages of sizable coverage in a cellular network and high data rate in deployable ad hoc network. It also enlarges the scope of communication for ad hoc network and improves the throughput for cellular network. Consequently, nodes in HWN can communicate with each other or access Internet ubiquitously. We also address the routing issues for HWN, because the routing protocol for HWN is different from those used in cellular network or ad hoc network. The dynamic adaptive routing protocol establishes a better path for the source to arrive at the destination across multiple hops or cellular network and provides appropriate QoS (quality of service) in HWN.Through simulation, we will demonstrate the merit of the HWN, proposed routing performance on HWN and overhead of control traffic. A performance analysis of the proposed protocol is depicted. The results of the analysis, and simulations, are presented and discussed.     

空中骨干网络路由协议改进设计

空中骨干网络由多个空中平台通过无线连接构成,并能够为各类中小型空中平台提供网络服务.空中骨干节点具有动态性,造成骨干网拓扑结构具有可变性,采用商用路由协议将会造成网络开销过大、无法维护正确的网络拓扑信息等问题.通过对空中骨干网络特点进行分析,在商用主动式路由算法的基础上进行跨层设计,并优化泛洪机制,实现了网络开销随着链路状态进行动态变化,利用较小的网络开销来维护准确网络拓扑结构.仿真结果表明,改进的路由协议基本满足空中骨干网的要求.     

A distributed protocol for dynamic address assignment in mobile ad hoc networks

A Mobile Ad hoc NETwork (MANET) is a group of mobile nodes that form a multihop wireless network. The topology of the network can change randomly due to unpredictable mobility of nodes and propagation characteristics. Previously, it was assumed that the nodes in the network were assigned IP addresses a priori. This may not be feasible as nodes can enter and leave the network dynamically. A dynamic IP address assignment protocol like DHCP requires centralized servers that may not be present in MANETs. Hence, we propose a distributed protocol for dynamic IP address assignment to nodes in MANETs. The proposed solution guarantees unique IP address assignment under a variety of network conditions including message losses, network partitioning and merging. Simulation results show that the protocol incurs low latency and communication overhead for an IP address assignment.     

OLSRv2压缩机制在自组织网络中的应用

尽管战术无线自组织网络正在向宽带高速传输技术发展,能够提供更多的带宽资源,但各种新的战术应用业务对带宽的需求发展更快,因而需要设计与高速传输特性相匹配的低开销先进路由机制。在这种新型的高速战术网络中,需要路由协议为指挥员提供本作战区域内的全局的战术单位连通拓扑的态势信息、提供能够更好地支持服务质量（QoS）的控制机制、能够更好地支持战术网络的拓扑优化控制、能够针对不同传输波束方向的链路分别实施功率控制、能够通过全局最短路径代价计算避免路由环路等。基于地址块格式压缩机制,优化链路状态路由协议版本2（0LSRv2）将能以较低的带宽开销满足这些设计要求。