网络编码调度策略的研究

网络编码是通信领域的一项重大突破,其基本思想是建立在网络信息流的基础之上,通过网络节点对来自不同链路的信息流进行编码处理,使其既能实现传统路由功能,又能实现对信息的编码处理。分析了等速率的网络编码调度策略,并把自适应传输技术应用到网络编码的调度策略,然后通过Matlab仿真分析,验证了自适应的网络编码策略可提高通信系统的网络编码增益、吞吐量和减少数据传输延时方面的贡献。     

基于图神经网络的网络性能智能预测

传统网络性能预测技术存在网络状态获取不够全面及网络性能评估准确性欠佳等问题，利用图神经网络学习推理网络关系数据的特点，结合捕获的网络全局信息，提出了一种基于图神经网络的网络性能智能预测方法。通过网络系统抽象及网络性能建模，将复杂的网络信息转化为形式化的图数据进行描述，利用图空域卷积处理图网络节点的消息传递过程，实现网络信息之间的关系推理，研究了实现网络性能预测的图神经网络模型，提出了一种能处理流量矩阵、网络拓扑、路由策略、节点配置的图神经网络体系结构，最后通过实验论证了模型能更好地实现包括时延、抖动和丢包率的网络性能的准确预测。     

基于增强学习的协作主动路由信息交换机制

分组交换网是当今全球通信基础设施的重要部分，IP网络终将与其他网络相互融合，演化成为新一代网络技术，现有路由协议的实现是单一的，并且将数据库、最优路径计算和网络状态分发机制捆绑在一起。主动路由选择是一个把上述困难作为目标的新路由选择策略。主动路由选择机制被设计用来提供基于用户服务模式的路由选择。本文提出了一种基于增强学习的协作主动路由信息交换机制，主动路由代理获悉网络基础结构不同属性的当前状态，并在这个基础上建立和维护路由表，实现主动路由选择机制。     

意图抽象与知识联合驱动的6G内生智能网络架构

6G将以智能网络为演进形式，具备内生智能、开放性的特征。智能网络标准化研究中强调了意图驱动网络对实现网络智能化的必要性。但目前基于意图的网络将意图理解为“What to do”而非“What you want”，利用知识定义网络（KDN）可在一定程度上根据“What to do”完成“How to configure the network”。基于此，提出了意图抽象与知识联合驱动的6G内生智能网络架构，旨在根据“Whatyouwant”实现“Howtoconfigurethe network”。首先，设计了意图抽象模块，通过意图获取、意图转译、意图映射和意图建模，从“What you want”获取“What to do”。其次，提出了认知模块，利用机器学习和逻辑推理联合动态优化获取网络知识，从而根据“What to do”完成“How to configure the network”。最后，介绍了支撑6G内生智能实现的意图映射、网络信息测量、网络策略生成、网络策略验证等关键技术及未来挑战。     

基于INT感知的5G核心网用户面流量调度系统

为解决5G移动数据流量激增和新型网络应用不断涌现给网络运维造成巨大压力的问题,设计并实现一个面向5G核心网用户面的流量调度系统,包含网络状态信息感知子系统和路由决策子系统。在网络状态信息感知子系统中,传统带内网络遥测方法带宽开销高,而且不是专门为无线网络系统设计的,此外,在5G核心网中应用带内网络遥测还面临测量精度不高、QoS无法保障等挑战。为此,提出了基于带内网络遥测的5G核心网用户面状态信息感知方案,将遥测信息插入GTP-U报文的扩展头部,实时检测UPF状态信息,实现网络状态动态随路测量。路由决策子系统实现了基于改进蚁群算法的流量调度算法,利用感知到的网络状态信息升级信息素函数更新方式,完成基于实时网络状态的路由决策。实际部署测试结果表明,网络状态信息感知子系统能正常感知网络信息,而且所做路由决策在时延、吞吐量和丢包率方面优于传统路由算法。     

知识定义的意图网络自治

通信网络的复杂性决定了意图网络自治是无法一蹴而就的,关键在于以全局视角,打通多个网络管控问题域,将网络规律、机理、策略凝练为知识,构建全场景资源调配的知识空间,最终实现意图网络的泛在智能化。围绕6G意图网络,将知识定义智能作为关键使能技术,以提高意图网络的感知和决策闭环能力,构建自学习、自运维的意图网络。实现完全的6G网络自治是一个长期目标,需要分步实现,从提供重复执行操作的替代方案,到执行网络环境和网络设备状态的感知和监控,根据多种因素和策略做出决策,以及有效感知最终用户体验,直到最后网络能够感知运营商和用户的意图,自我优化和演进。     

ASON技术分析及其在SN16000中的应用

新一代的光网络已经从一个静态无声的，非智能的网络逐渐演变成为动态灵活的，自动路由的网络，光网络智能化的一个重要的任务就是引人更多功能和智能管理实现网络资源管理智能化，这就是ASON的含义。ASON促进了传送网从承载网向业务网的转变，降低了带宽成本，能提供如TLS，BOD，OVPN，Diffsc州（差异化服务)等的增值业务，而网络的发展趋势是核心网中业务层和传送层独立发展，而边缘网中业务层和传送层趋于融合，完成向全光网络演进。对于网络运营商最大的挑战莫过于同时将接人层一电层面和光层面智能化并且保持二     

智能大学安防智能化系统研究

安防智能化系统是智能大学系统的重要组成部分。文章通过对无线传感器网络的研究,提出基于无线传感器网络的安防智能化系统研究方案,并对方案中涉及到的系统特征、网络架构、硬件组成、路由协议设计等进行深入研究。由于该系统对网络的稳定性要求较高,而且网络中需要传输的参数较多,因此,在最小跳数路由协议的基础上,对网络的路由协议提出了改进,将节点剩余电池能量考虑其中,且以限制型广播方式广播路由信息．从而可以提高路由的有效性,大大降低数据传输的丢包率。     

支持DiffServ的流量工程体系中最小化抢占的路径选择策略

在支持具有不同优先级和不同Qos需求的多业务网络中，抢占是带宽分配和管理的有效策略，但抢占也对网络造成了振荡。在路由策略中引入抢占信息可最小化重路由，提高网络的稳定性。本文在分析MPLS网络现有路径选择策略和抢占策略的基础上，提出一个最小化抢占的带宽约束路径选择算法。其基本思想是在路径选择中考虑低优先级LSP的资源预留信息，在链路开销函数中引入抢占信息即将被抢占的带宽和将被影响的最高优先级。我们的算法能在最小化抢占和重路由的同时实现负载均衡，有效地改善全局网络性能。     

浅析计算机网络路由优化及其优化算法

计算机网络路由可以实现互联网络端口的连接,并能够有效满足不同网络之间的信息传送,在科学技术日益提升的今天,计算机网络的应用越来越普遍,使用计算机网络的人数也在逐年增加,大规模化的计算机网络覆盖也给我国当前的计算机网络路由工作带来了更大的压力与挑战。对计算机网络路由进行优化的同时也能够进一步提高计算机网络资源的有效利用,改善计算机网络对于用户的服务质量。本文以网络路由及多样性种类为切入点,为如何加强计算机网络路由的服务功能、进一步提高计算机网络信息传输的稳定性与安全性等问题提出计算机网络路由优化及其优化算法。     

A New Energy Efficient Hierarchical Routing Protocol for Wireless Sensor Networks

Wireless sensor networks consist of low cost sensor nodes which have limited power supplies, memory capacity, processing capability and transmission rate. Sensor nodes gather information from the environment and send the collected information to base station with help of a routing cooperation. Because of limited resources in Wireless Sensor Networks, fulfilling these routing operations is a major problem. Routing protocols are used to perform these operations. The most important thing by considering while these protocols are designed is energy efficiency. Because wireless sensor networks are widely used in intelligent systems, the energy efficiency of these networks is very important in IoT. Researchers have proposed several hierarchical routing protocols such as LEACH, PEGASIS, TEEN and APTEEN. In this study, an energy efficient routing protocol is developed which is more efficient than currently avaliable routing protocols. The developed protocol involves mapping of the network, sleep–wake/load balancing, data merge processes. The proposed protocol gives better results than other protocols in number of surviving nodes and amount of energy consumed criterias.     

基于无线传感器网络的海水检测系统

针对海水检测周期长、范围小的特点,提出了使用无线传感器网络的海水指标实时在线检测方案。研究了精确检测的方法与算法,探讨了无线传感器网络节能路由协议。系统综合运用无线传感器智能信息处理技术、远程GPRS无线数据通信技术以及基于Internet显示平台的监测点管理查询技术,将功能相同或不同的传感器构成智能化传感器网络,从而全面提升了系统的自动化与监测水平。模拟实验结果表明系统具有良好的海水定量检测能力。     

Evaluating the impact of stale link state on quality-of-servicerouting

Quality-of-service (QoS) routing satisfies application performance requirements and optimizes network resource usage by selecting paths based on connection traffic parameters and link load information. However, distributing link state imposes significant bandwidth and processing overhead on the network. This paper investigates the performance tradeoff between protocol overhead and the quality of the routing decisions in the context of the source-directed link state routing protocols proposed for IP and ATM networks. We construct a detailed model of QoS routing that parameterizes the path-selection algorithm, link-cost function, and link state update policy. Through extensive simulation experiments with several network topologies and traffic patterns, we uncover the effects of stale link state information and random fluctuations in traffic load on the routing and setup overheads. We then investigate how inaccuracy of link state information interacts with the size and connectivity of the underlying topology. Finally, we show that tuning the coarseness of the link-cost metric to the inaccuracy of underlying link state information reduces the computational complexity of the path-selection algorithm without significantly degrading performance. This work confirms and extends earlier studies, and offers new insights for designing efficient quality-of-service routing policies in large networks     

Link State Routing Based on Compressed Sensing

In table routing protocols such as link state routing, every node in the network periodically broadcasts its link state and the state of its neighbors. These routing updates result in the transmission of a large number of packets. Some of these packets contain correlated or even redundant data which could be compressed if there is central management in the network. However, in autonomous networks, each node acts as a router, in which case central coordination is not possible. In this paper, compressed sensing is used to reduce routing traffic overhead. This can be done at nodes which have greater processing capabilities and no power consumption limitations such as backbone nodes in wireless mesh networks. A method is proposed to select a subset of nodes and thus a subset of links to probe their state. The sensed states are encoded to generate a low dimension sampled vector. This compressed link state vector is broadcast to the entire network. Nodes can then reconstruct link states from this vector using side information. Performance results are presented which demonstrate accurate anomaly detection while adapting to topology changes. Further, it is shown that a proper choice of weighting coefficients in the sampling process can improve detection performance.     

Handoffs in Cellular Wireless Networks: The Daedalus Implementation and Experience

Network protocols in cellular wireless data networks must update routes as a mobile host moves between cells. These routing updates combined with some associated state changes are called handoffs. Most current handoff schemes in wireless networks result in data loss or large variations in packet delivery times. Unfortunately, many applications, such as real-time multimedia applications and reliable transport protocols, adapt to long term estimates of end-to-end delay and loss. Violations and rapid fluctuations of these estimates caused by handoff processing often result in degraded performance. For example, loss during handoff adversely affects TCP performance [4], and high packet loss and variable delays result in poor real-time multimedia performance. In this paper, we describe a multicast-based protocol that eliminates data loss and incurs negligible delays during a handoff. The basic technique of the algorithm is to anticipate a handoff using wireless network information in the form of received signal strengths and to multicast data destined for the mobile host to nearby base stations in advance. This routing, combined with intelligent buffering techniques at the base stations, enables very rapid routing updates and eliminates data loss without the use of explicit data forwarding. We have implemented this protocol using IP Multicast and Mobile IP-like routing. In our implementation, handoffs typically take between 8 and 15 ms to complete and result in no data loss.     

一种利用跨层优化策略选择中继的协作路由算法

该文提出了一种新的中继选择的协作路由算法,该算法利用网络的路由包获得信道的信息,通过分布式计算从候选中继集合中选择出一个最佳中继转发数据。在分层的无线网络中,中继选择的实现包括了时间同步和跨层优化等。仿真结果表明,相对于DSDV协议,该文所提出的算法有效地提高了数据包的递交率并有效地降低了网络的时延。     

Shared protection in mesh WDM networks

This article introduces the design principles and state-of-the-art progress in developing survivable routing schemes for shared protection in mesh WDM networks. This article first gives an overview of the diverse routing problem for both types of protection in mesh networks, path-base and segment shared protection; then the cost function and link state for performing diverse routing are defined by which the maximum extent of resource sharing can be explored in the complete routing information scenario. Review is conducted on the most recently reported survivable routing schemes along with state-of-the-art progress in diverse routing algorithms for segment shared protection. The following three reported algorithms are discussed in detail: iterative two-step-approach, potential backup cost, and maximum likelihood relaxation.     

An ACO and position information based intelligent QoS routing mechanism in MANET

Quality of service (QoS) routing technology, which can find the available route, is an important way to realize the end-to-end QoS provisioning for networks. Intelligent routing discovery, establishment and maintenance, which take use of ant colony algorithm, have been widely researched in the past years. But the ant colony algorithm has two obvious shortcomings, which are low convergence rate and algorithm stagnation in local optimum. As the topology of mobile ad hoc network (MANET) is always changing, the information of network status is hard to collect in time. So the enhancement of the convergence rate of the QoS routing algorithm is quite important in MANETs. Based on the AntHocNet algorithm previously designed for ad hoc networks, this paper proposes a position-based intelligent QoS routing algorithm. The position constraints are added in the procedures of tabu list forming and pheromone updating. Compared with AntHocNet, the proposed mechanism can greatly reduce the convergence rate in the premises of searching an available path with QoS guarantee according to the simulation results.     

Information efficiency of multihop packet radio networks with channel-adaptive routing

This paper analyzes the benefit of adaptive routing based on knowledge of the channel state information in multihop, ad hoc wireless networks that use direct-sequence code-division multiple access. Cross-layer, channel-adaptive routing exploits the inherent spatial diversity of multihop wireless networks to select links with favorable channel conditions. The information efficiency, an extension of a previously used measure called expected progress, is used to evaluate performance. Results show that, combined with adaptive modulation, adaptive routing can improve performance in ad hoc networks by a factor of four to five in channels with Rayleigh fading and lognormal shadowing. The lack of position information in the routing decision would reduce performance by 25%. New approaches to channel-adaptive routing that enable rapid adaptivity to channel conditions are discussed.