Mobility label based network: Mobility support in label switched networks with multi-protocol BGP

To support mobility the network control plane is required to detect changes in the mobile node’s location and distribute the new location information throughout the network thus enabling the forwarding plane to deliver traffic in an optimal manner. The network responsiveness to the mobile node movements can be generally thought of as the time elapsed between the moment the node’s location in the network has changed and the moment the reception of packets in the new location has resumed. This paper outlines an approach to handling the user mobility at the network layer in the context of multi-protocol label switched networks (MPLS). This new approach does not rely on the existing IP mobility management protocols such as Mobile IP and is instead based on the combination of multi-protocol BGP (MP-BGP) and MPLS. This paper proposes to introduce new protocol elements to MP-BGP to achieve mobility label distribution at the network control plane and the optimal packet delivery to the mobile node by the network forwarding plane using MPLS regardless of the IP protocol addressing and the associated logical network topology.     

基于缓存与指针推进的混合移动性管理策略

提出了一种将缓存策略与指针推进策略结合的混合位置管理策略(记为HCF策略),通过利用移动用户移动的移动性以及接受呼入的局部性,在缓存信息失效的情况下,可通过遍历起始于缓存中的推进指针链来获得移动用户的位置信息,从而避免直接访问归属位置寄存器HLR(Home Location Register)数据库。因此,该策略可有效的减少对HLR的访问,减少位置管理中的通信流量。实验结果显示,当一个移动用户的呼叫-移动率较高CMR(Call-to-Mobility Ratio)或HLR的通信流量较大时,提出的策略优于基本策略和现有的缓存策略。     

基于多Agent的策略驱动网络管理体系结构

通过对基于策略的管理技术和基于智能Agent分布式系统地分析,提出了一种策略驱动的基于多Agent的网络管理体系结构,利用了策略和Agent多种特性,适合实现面向服务和自治管理的分布式管理系统。     

Optimized mobility management for RPL/6LoWPAN based IoT network architecture using the firefly algorithm

RPL (Routing Protocol for low-power and Lossy Networks) is a new attractive model that secures the networks from different routing risks. The dynamic environment and limited resources motivated the research towards identifying a stable, reliable, energy efficient, and scalable routing design. IPv6 over low-power Wireless Personal Area Network (6LoWPAN) is a standard RPL IPv6 routing protocol that provides Low power and Lossy Networks (LLNs) interoperability. In this research work, an energy efficient and optimization-based mobility management framework in RPL routing protocol was proposed (mRPL-based firefly optimization algorithm) to achieve a reliable and stable protocol. From the results, it can be inferred that the proposed system (mRPL+firefly optimizer) showed better performance with regard to the Packet_Delivery_Ratio (PDR), number of hops, End_To_End delay and power consumption when compared to existing systems: RPL, mRPL, mRPL+PSO, and mRPL+ACO. The experimental outcome showed that the proposed system improved the PDR on an average of 2.31% in comparison with existing systems.     

基于包转发的电话会议系统的研究与实现

针对目前电话会议系统应用的普及以及所存在的一些弊端,提出一种新型的电话会议实现方式--基于包转发技术的电话会议技术实现方式.包转发技术不对通信双方的语音和信令数据作任何处理,只将信息透明的传输到通信对方端,而语音和信令数据的处理完全交给计算机上的软件来完成.给出了包转发及其相关的技术,在此基础上设计并实现了一种基于PSTN信令和以太网技术的电话会议基础平台.对系统进行了相关的测试,测试结果表明,所设计的系统可实现电话会议系统的基本功能.     

Assured forwarding fairness using equation-based packet marking and packet separation

Fairness is one of the important problems in assured forwarding (AF) performance in the differentiated services (DiffServ) framework [An architecture for differentiated services, RFC 2475, IETF, December 1998; A two-bit differentiated services architecture for the Internet, Internet-draft, draft-nichols-diff-svc-arch-02.pdf, IETF, April 1999]. In this paper we present a two-part solution for the fairness problem in AF. The first part is a new packet marking algorithm called equation-based marking (EBM) and is based on the TCP model given by Padhye et al. [Modeling TCP throughput: A simple model and its empirical validation, in: Proceedings of ACM SIGCOMM ’98, October 1998]. EBM is to handle the problems found in other marking schemes regarding fairness among heterogeneous TCP flows through a tight feedback-loop operation and adaptation of the packet marking probability to network conditions. The second part is called packet separation used at routers to handle the fairness between responsive and non-responsive traffic. We evaluate the performance of a packet marker that uses EBM as the marking algorithm using in-depth simulation. We prove, analytically and using simulation, the correctness of the marking algorithm and compare it with other marking schemes for different network scenarios. We also use simulation to show the effectiveness of the packet separation mechanism in solving the fairness problem between responsive and non-responsive traffic. Our evaluation results demonstrate the effectiveness of EBM along with packet separation in providing the required fairness among heterogeneous flows and ensuring protection against non-assured traffic.     

Active network architecture and management

Access and retrieval of meteorological and oceanographic data from heterogeneous sources in a distributed system presents many issues. There are a number of features of the TEDServices system that illustrate active network management for such data. There is a self-aware or intelligent aspect with respect to the mechanisms for shutdown, data ordering, and propagation of data orders. Intelligent cache management and collaborative application sharing process are other features of the active network management. Additionally a very important capability is the implementation of resumable object streams, which allows either the client or server side of a request to lose network connection, regain it, and the request will continue where it left off. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 1123–1138, 2007.     

基于J2EE规范的电信综合网管架构设计

J2EE（JAVA 2 Enterprise Edition）是SUN公司提出的JAVA技术规范,它也是一个分布式系统的设计和开发环境,提供了基于组件的,以服务器为中心的多层应用体系结构.网络管理系统是对计算机网络、设备、软件等进行管理的软件系统,其主要功能包括性能管理、配置管理、故障管理、记帐管理和安全管理.在J2EE规范下实现网管系统可以很好的满足组件化、易于构建、分布部署等要求.针对J2EE的特点,根据TMN网管系统的要求,结合实例,本文探讨了如何在J2EE规范下进行电信综合网管平台的架构设计.     

改进的基于网络编码中继转发方案

针对双向中继网络中传统中继转发协议放大信号的同时放大了噪声、可能转发错误的解码信号、中继判决结果不可靠等问题,提出两种基于互信息转发(MIF)的网络编码中继转发方案。首先,中继节点转发来自两个源端信息的硬判决结果;同时还转发其可靠度;然后,接收端将来自中继节点转发的信号及其可靠度和源端信号合并,并对合并结果进行检测和判决。详细推导了所提出两种方案接收端信噪比(SNR)的表达式,并在加性高斯白噪声(AWGN)信道两种仿真条件下进行数值仿真;同时分别在AWGN信道和瑞利信道中对各种方案误码率进行蒙特卡罗仿真。结果表明在两种信道条件下所提出方案在误码率(BER)性能上较估计转发(EF)方案相比分别有约1 dB和1~2 dB的增益。仿真实验结果说明基于MIF的网络编码方案在双向中继网络中继转发中对系统的误码性能有显著提升效果。     

Fast binary and multiway prefix searches for packet forwarding

Backbone routers with tens-of-gigabits-per-second links are indispensable communication devices to deploy on the Internet. The IP lookup operation is the most critical task that must be improved in routers. In this paper, we first present a systematic method to compare prefixes of different lengths. The list of prefixes can then be sorted and stored in a sequential array, which is contrary to the linked lists used in most of trie-based structures. Next, fast binary and multiway prefix searches assisted by auxiliary prefixes are proposed. We also developed a 32-bit representation to encode the prefixes of different lengths. For the large routing tables currently available on the Internet, the proposed multiway prefix search can achieve the worst-case number of memory accesses of three and four if the sizes of the CPU cache lines are 64 bytes and 32 bytes, respectively. The IPv4 simulation results show that the proposed prefix searches outperform the existing IP lookup schemes in terms of lookup times and memory consumption. The simulations using IPv6 routing tables also show the performance advantages of the proposed binary prefix searches. We also analyze the performance of the existing lookup schemes by concurrently considering the lookup speed, the update speed, and the memory consumption. Although the update speed of the proposed prefix search is worse than the dynamic routing table schemes with log(N) complexity for a table of N prefixes, our analysis shows that the overall performance of the proposed binary prefix search outperforms all the existing schemes.     

Agent mobility architecture based on IEEE-FIPA standards

Mobile agents are autonomous software entities driven by a set of goals and tasks. Reactivity, social ability, autonomy, the ability to move to different network locations, and the weak agent notion of proactiveness, allow for autonomous processing of distributed information according to their environment (context awareness).Although agent mobility has been devised for homogeneous environments, deployment of agent mobility in heterogeneous environments has been hindered by the absence of a common set of interoperation rules and ontologies for different agent middlewares.In this article, an agent migration model based on the communication standards of the IEEE-FIPA organisation is proposed. The approach described encompasses the definition of several specifications to achieve interoperability in the migration process in heterogeneous environments.The model provides a basic and extensible common migration process, which is flexible enough to support different kinds of migration methods and future upgrades. It is completely independent of any specific middleware implementation.     

基于网络终端支持的NDN移动性管理机制

命名数据网（named data networking,NDN）作为一种新型的互联网架构,旨在应对日益增长的数据流量。基于其消费者驱动的内容检索模型,NDN自然地支持消费者移动性。然而生产者移动性仍然是一个具有挑战性的问题,需要额外的机制来提高生产者移动期间的数据可用性。针对该问题,提出一种可扩展的移动管理机制来支持生产者移动性。该机制利用网络终端在基于名称的NDN转发平面上建立了临时转发路径,并设计了缓存与重传机制支持时延容忍和时延敏感的应用数据流。最后在ndnSIM中建立了一个全面的仿真环境,对所提方案与现有解决方案进行了评估和比较。仿真结果表明,该机制能够充分支持生产者移动性。当速度为30 m/s时,丢包率仅为3.0%,平均传输延时为352.1 ms。此外,支持生产者移动性所需的额外消耗于对于方案相比降低了49.18%。     

基于AI的LEO卫星网络资源管理架构设计

低轨(LEO)卫星作为天地一体化信息网络中天地信息传输的重要枢纽,具有规模大、链路损耗小、传输时延低等特点,已成为天地一体化信息网络研究领域的热点。提出了一种基于人工智能(AI)的LEO卫星网络资源管理架构设计,基于天地一体化信息网络架构,在地面引入软件定义网络(SDN)实现对卫星网络资源状态信息进行实时观测,再结合网络大脑(Network Mind)并应用人工智能算法学习得到资源分配优化策略,实现高效信息传输。     

机会网络中基于陌生节点的竞争转发策略

针对机会网络中存在自私节点导致消息的传送成功率偏低、开销大、延迟高,考虑到节点在其社会属性存在的情况下,提出基于陌生节点的竞争转发算法—BSCP(based on stranger competition algorithm).重点分析消息转发过程中利用节点的属性制定相应的转发策略,通过节点的陌生性,设置陌生节点在整个环境中的比例值,计算节点相遇的最大陌生值并排序,设计节点竞争策略使得数据转发成功率提高.仿真验证了BSCP算法的有效性,与STRON、Epidemic及BSIF等算法相比,该算法能有效保证消息传送成功率,减少由于节点自私性产生的消息丢失和碰撞现象,提高吞吐量,降低网络开销和延迟.     

基于网络处理器的并行包分类方法

在大型网络中大量的规则数量会导致位向量（BV）算法的位向量过长和稀疏,要在网络处理器中实现BV算法需要大量的存储资源,而且多次存储读取也降低了算法匹配效率。针对BV算法位向量的问题,将Tuple空间分割思想与BV算法相结合缩短了位向量长度,充分利用网络处理器的并行处理机制和硬件加速单元,提出了一种适用于网络处理器的改进算法——Tuple-BV算法。该算法的元组分割缩短了位向量的长度,减少了位向量的存储空间和读取次数。通过对数据包处理延时的实验比较,当较多规则时,Tuple-BV算法在最大延时和平均延时指标上优于BV算法。     

基于转发效应的自媒体网络舆情扩散

随着无线网络技术的发展与手机网民人数的激增,以微信、微博等新媒体为平台的自媒体网络舆情逐渐取代传统媒体舆情,成为舆论场上的主导力量,并对社会的稳定产生了重要影响.基于此,首先界定自媒体网络舆情转发网络的相关概念,论述转发网络的转发效应;然后剖析自媒体网络舆情转发效应的影响因素,构建基于转发效应的自媒体网络舆情扩散模型,并在此基础上,对舆情扩散模型进行了仿真分析.通过仿真分析发现,转发网络中的超级群组是自媒体网络舆情迅速扩散的中心和节点,使得自媒体网络舆情扩散出现了明显的动态舆情级联特征,进而使其在出现、增长与稳定等阶段具有发散性特征,并以合并、超级群组和集中式拓扑结构等效应形式进行着扩散和传播.     

Mesh网络中基于效用转发的路由恢复算法

在文献[10]的无线M esh网络路由算法的基础上,提出一种改进的基于效用转发的路由快速恢复算法,根据不同网络环境下影响效用值的各因素所占权重不同的特点,利用节点的历史通信数据,动态获取权重值,使算法能更好适应真实的网络环境;综合利用网络时延、节点效用值和节点之间的跳数,选择最优的下一跳转发节点,减少网络中不必要的时延增加和资源浪费.ONE仿真结果表明,与其它4种路由协议进行对比分析,该算法能够提高数据包的转发效率,提升网络的性能.     

拍卖机制的包转发路由模型及其仿真研究

本文结合拍卖博弈的思想,考虑到对整个传感器网络路由有影响的各种有关参数,给出了一种以拍卖博弈形式的包转发路由算法流程,通过该算法流程可以达到高效地促进多个节点的相互合作,从而有效地减少控制包在传输过程中的次数,全面有效地实现多个分布式的科学控制,并充分利用NS2平台作为对拍卖博弈算法进行仿真验证,对整个实验结果进行对比分析。     

mesh网络中基于效用转发的网络编码算法

在已有的无线Mesh网络路由算法的基础上,针对网络的动态变化性和差异性等因素带来的问题进行了研究,提出一种基于效用转发的网络编码算法.首先利用节点间的历史通信数据,动态获取不同网络环境下影响效用值的各因素所占的权重值;然后在簇头节点和汇聚节点处进行二维随机线性网络编码,结合节点的剩余能量、效用值和丢包率判断节点能否进行编码,并且采用编码包优先传输的策略转发数据包;最后综合利用网络时延、效用值和节点间的跳数,选择最优的下一跳转发节点.仿真结果表明,该算法能更好地提升数据包的转发效率,降低传输时延,提高网络的性能.