基于节点密度的混合式多信道分配算法

为了减小无线传感器网络中的同频干扰和避免网络堵塞问题,文章提出了一种基于节点密度的混合式多信道分配算法。该算法通过考虑链路干扰以及节点密度等因素,来解决局部严重同频干扰问题,实现各信道负载均衡,减少网络阻塞。仿真实验结果分析表明,该算法能有效地解决网络中同频干扰问题,较好地均衡各信道的网络负载,在数据业务较重的情况下,网络性能仍比较良好。     

模糊聚类CIAP在雷达组网中的应用

随着雷达网络传输技术的发展,雷达网络中的数据拥塞和流量分配不均衡问题亟待解决.文中针对多个被覆线与无线AP所组成的雷达传输网络中的流量分配不均衡问题,对多链路负载均衡算法(CIAP)中的任务调度算法进行改进.算法依据网络传输链路本身的固有特性,在进行链路碎片调度时,采用模糊聚类的思想对任务调度算法进行改进,该算法根据网络中各链路的剩余带宽和链路时延对负载较大的链路的路由碎片进行实时调度.实验结果表明,与传统的基于循环招标任务调度的多链路负载均衡算法比较,改进的算法能够迅速高效地均衡雷达网络中的链路负载.     

一种基于信道阻力的Ad hoc网络多路径路由算法

该文提出了一种基于信道阻力的Ad hoc网络多路径动态源路由算法。算法中定义了信道阻力的概念,并以信道阻力为依据来进行多条路径的流量分配,由于信道阻力计算中综合考虑了链路质量的各个度量参数,因此能够根据各条路径的传输能力合理分配数据流量。NS2环境下的仿真表明,新算法能够有效地平衡网络负载,提高网络的吞吐量。     

一种适用于星地网络的流量负载均衡算法

在星地网络的背景下,为了降低由于地面网络链路负载过高导致的传播时延,提出了一种适用于星地网络的负载均衡算法。算法基于网络的链路容量设置一个链路资源利用率作为阈值,当发现路径出现过载的时候分成两步进行路径的预规划：第一步,运用蚁群算法为链路过载的数据流选择其他的路径,以满足地面网内部的负载均衡;第二步,如果仍出现链路超阈值的情况,通过卸载延迟容忍数据流来执行地面与卫星网络之间的负载均衡。仿真结果表明,设定自适应的过载阈值可以有效降低链路的拥塞,与现有算法相比该算法不仅可以更加均匀地分配地面网络中的流量,而且借助卫星网络使地面网络的平均时延降低了18.3%,提高了网络的服务质量。     

基于BIG-IP多链路负载均衡技术的应用

针对当前广泛使用的多链路技术,研究了多链路网络的运行机制,对多链路的流量特性、负载分配策略进行了分析。根据用户访问互联网的状况在多条链路之间动态而透明地分配流量和负载,有效地实现了多链路的负载均衡和冗余备份。本文基于某企业网络配置实例,对链路负载均衡技术的实现过程和它所带来的变化进行了细致的分析。     

802.11无线网状网中基于时频信道的准动态信道分配算法

该文首次在多天线多信道802.11无线网状网中提出了时频信道的概念。时频信道是通过在时间和频率两个维度划分无线资源取得的。这种划分方法增加了信道数量,使信道划分更加精细,为提高系统的信道利用率做了准备。在时频信道的基础上,提出了准动态信道分配算法。该算法可以和现有的固定信道分配算法结合,实现准动态信道分配,根据链路上负载变化,取得最大的吞吐量。该算法先根据固定信道分配算法为各链路分配相同数量的时频信道,剩余部分当作公共信道。在通信过程中,各链路首先使用分配给自己的信道和空闲的公共信道。如果分配给一个链路的信道不够,且别的链路上的信道有空闲,该链路还可以暂时使用这些空闲信道。理论分析和仿真结果证明该算法可以有效提高系统的吞吐量。     

无线传感器网络中支持并行传输的信道与功率联合优化博弈算法

针对无线传感器网络中干扰日益增大引起网络容量下降、能耗增加的问题,该文建立了信道分配与功率控制联合优化博弈模型。在该模型中链路将既能保持自身成功传输又不影响其它链路传输的信道作为可选信道,以实现链路的并行传输。继而基于该模型设计了一种支持并行传输的信道分配与功率控制联合优化博弈算法(JCPGC)。该算法利用最佳响应策略对模型求解,并通过超模博弈等理论证明了JCPGC能够收敛到纳什均衡。此外,该算法充分考虑信道分配和功率控制之间独立又相互影响的关系提高了网络容量。仿真实验结果表明,JCPGC具有大容量、低干扰和低能耗的特性。     

无线Mesh网络集中式信道分配算法设计

以集中式无线Mesh网络(WMN)为基础,分析和研究了传统多信道分配算法,并在此基础上提出了以节点优先级和分组为特点的多接口多信道分配算法(Channel Assignment based on Rank of Node and Link group,CAR-NL),该算法结合节点分级和链路负载预期评估机制,通过节点链路分组按级分配信道。通过仿真实验表明,该算法能有效提高无线Mesh网络多业务流并发执行时系统整体吞吐量,并实现较低的丢包率。     

FALB:一种FC协议链路聚合算法

链路聚合是一种通过将多条物理链路捆绑成一条逻辑链路来增加带宽的常用技术,但是在基于光纤通道（fibre channel,FC）协议的交换网络中,随着转发流量区域的不断集中,传统静态链路聚合算法存在负载均衡性差、可靠性低的问题。因此提出了一种基于FC协议的动态负载均衡（flow adaptive load balancing, FALB）链路聚合算法,可以实现对流量的动态自适应匹配以及断链可重连保护机制。结果表明,该算法机制相较于静态负载均衡的算法设计,可以将有效带宽比最终收敛到 95%以上,有效提升聚合链路的负载均衡特性和可靠性。     

无线网状网射频链路的信道分配算法

研究了无线网状网络节点的接口异构对网络容量的影响.提出了一种新颖的以射频链路为信道分配对象的接口和信道联合分配的分布式贪婪最大算法.该算法以队列长度为权的射频链路吞吐量之和最大为目标,寻找自适应于网络拓扑和流量变化的分布式接口与信道联合分配方案.算法分析指出本算法与非接口异构的Dist. Greedy算法的时间复杂度相当,NS2仿真结果表明网络容量有明显提升.     

无线局域网中的负载均衡技术

随着无线局域网扩展服务集中的终端（STA）的移动和无线信道的时变，各个接入点（AP）上的负载会出现差异，需要加强负载均衡，平衡各个AP的差异，以达到最大化的网络资源利用。无线局域网中的负载均衡算法可以采用STA／AP主控负载均衡或接入式／切换式负载均衡技术。在时分双工的时分同步码分多址（TD—SCDMA）系统中，由于系统在最小资源单位和媒体访问机制等方面的差异，负载均衡可以在小到时隙和码道，大到终端和小区等不同的级别上进行，体现码分多址（CDMA）和时分双工（TDD）的特点，具体方式更加灵活多样。     

Load-balancing in MANET shortest-path routing protocols

Mobile ad hoc networks (MANET) are infrastructure-less networks, dynamically formed by an independent system of mobile nodes that are connected via wireless links. Because routing is performed by nodes with limited resources, load should be efficiently distributed through the network. Otherwise, heavily-loaded nodes may make up a bottleneck that lowers the network performances by congestion and larger delays. Regrettably, load-balancing is a critical deficiency in MANET shortest-path routing protocols, as nodes at the center of the network are much heavily-loaded than the others. Thus, we propose, in this paper, load-balancing mechanisms that push the traffic further from the center of the network. Basically, we provide novel routing metrics that take into account nodes degree of centrality, for both proactive and reactive routing protocols. Simulations show that the proposed mechanisms improve the load distribution and significantly enhance the network performances in terms of average delay and reliability.     

OBS中基于优先级与负载均衡的偏射路由算法

为了解决偏射算法在偏射控制七的问题,提出了一种基于优先级与负载均衡的偏射路由算法.当冲突发生时,分割优先级低的突发数据包;将冲突部分的突发包偏射到空闲的链路上,并在空闲的链路中选择若干条"当前最大剩余跳数小于源-目的节点的最大跳数"的路由作为候选路由;最后,在这些候选路由中选择一条可以使网络中各链路使用波长数的统计方差...     

Virtual channel load-balanced routing algorithm for Torus networks

In order to improve the network performance furthermore,a routing algorithm for 2D-Torus is investigated from the standpoint of load balance for virtual channels.The 2D-Torus network is divided into two virtual networks and each physical channel is split into three virtual channels.A novel virtual channel allocation policy and a routing algorithm are proposed,in which traffic load is distributed to those three virtual channels in a more load-balanced manner by introducing a random parameter.Simulations of the proposed algorithm are developed with a SystemC-based test bench.The results show that compared with the negative first for Torus networks(NF-T) algorithm,the proposed algorithm can achieve better performance in terms of network latency and throughput under different traffic patterns.It also shows that a routing algorithm with load balance for virtual channels can significantly improve the network performance furthermore.     

一种基于改进蚁群算法的选播路由算法

为了在网络负载较大的情况下实现多目标多路径的选播路由,该文根据蚂蚁寻径与选播路由的相似性,提出了一种基于改进蚁群算法的选播路由算法。在运用数据包传输的历史信息来模拟路径信息素的基础上,增加了目标地址泛洪负载信息来模拟食物气味散发的过程,使得各个节点可以获得服务器和链路的最新信息。节点根据路径上的信息素、食物的气味以及链路的可见度等综合生成概率表,作为后继蚂蚁路径选择的依据。运用NS-2对该算法进行仿真,测试结果表明它可以减少传输时延,降低服务器负载的波动幅度,实现链路的负载均衡,增加网络的容量,提高选播服务的可扩展性。     

Design and Evaluation of Multichannel Multirate Wireless Networks

In a multirate wireless network, low data rate nodes consume proportionately more channel resources than high data rate nodes, resulting in low overall network performance. The use of multiple non-overlapping frequency channels in multirate wireless networks can overcome the performance degradation by having nodes communicate on different channels based on their data rates. However, no effort has been invested to utilize the multiple channels for a multirate wireless network. In this paper, we introduce the Data Rate Adaptive Channel Assignment (DR-CA) algorithm for a multichannel multirate single-hop wireless network to provide higher network throughput and network efficiency. The main idea is to assign links having same or comparable data rates on the same channel to minimize the wastage of channel resources due to interference between high data links and low data rate links. We also design a new Intermediary Multichannel Layer (IML) which resides between network layer and link layer, at which we implement the DR-CA algorithm. The IML design requires no modifications to the underlying MAC layer and upper layers of the network stack. To evaluate the proposed algorithm we define new performance metrics—channel efficiency and network efficiency for a multichannel multirate wireless network. Using OPNET simulations, we show that the multichannel enhancement using our proposed algorithm provides significant performance improvement in terms of network throughput, channel efficiency, and network efficiency over existing approaches in multirate wireless networks. Under heavy load condition, the network efficiency using DR-CA algorithm reaches 90% of the maximum limit. To the best of our knowledge, this is the first work to utilize the benefits of multiple channels in the multirate wireless network environment.     

A limited resource vector load-balancing algorithm for softswitch-based heterogeneous clustered media server

I. Introduction NGN (Next Generation Network) that can sup- port multimedia services has become a research hotspot in telecom and computer field in recent years. In the NGN architecture, multimedia service platform includes many kinds of devices[1]. As the device to provide media resource data and multime- dia operation environment under the control of softswitch device, media server is a key device on multimedia service platform. The media server un- der the control of softswitch device i…     

Low-Complexity Load Balancing with a Self-Organized Intelligent Distributed Antenna System

A high call blocking rate is a consequence of an inefficient utilization of system resources, which is often caused by a load imbalance in the network. Load imbalances are common in wireless networks with a large number of cellular users. This paper investigates a load-balancing scheme for mobile networks that optimizes cellular performance with constraints of physical resource limits and users quality of service demands. In order to efficiently utilize the system resources, an intelligent distributed antenna system (IDAS) fed by a multi base transceiver station (BTS) has the ability to distribute the system resources over a given geographic area. To enable load balancing among distributed antenna modules we dynamically allocate the remote antenna modules to the BTSs using an intelligent algorithm. A self-optimizing network for an IDAS is formulated as an integer based linear constrained optimization problem, which tries to balance the load among the BTSs. A discrete particle swarm optimization (DPSO) algorithm as an evolutionary algorithm is proposed to solve the optimization problem. The computational results of the DPSO algorithm demonstrate optimum performance for small-scale networks and near-optimum performance for large-scale networks. The DPSO algorithm is faster with marginally less complexity than an exhaustive search algorithm.     

A load-balancing spare capacity reallocation approach in the next-generation SONET metro networks

The next-generation SONET metro network is evolving into a service-rich infrastructure. At the edge of such a network, multiservice provisioning platforms (MSPPs) provide efficient data mapping enabled by Generic Framing Procedure (GFP) and Virtual Concatenation (VC). The core of the network tends to be a meshed architecture equipped with Multi-service Switches (MSSs). In the context of these emerging technologies, we propose a load-balancing spare capacity reallocation approach to improve network utilization in the next-generation SONET metro networks. Using our approach, carriers can postpone network upgrades, resulting in increased revenue with reduced capital expenditures (CAPEX). For the first time, we consider the spare capacity reallocation problem from a capacity upgrade and network planning perspective. Our approach can operate in the context of shared-path protection (with backup multiplexing) because it reallocates spare capacity without disrupting working services. Unlike previous spare capacity reallocation approaches which aim at minimizing total spare capacity, our load-balancing approach minimizes the network load vector (NLV), which is a novel metric that reflects the network load distribution. Because NLV takes into consideration both uniform and non-uniform link capacity distribution, our approach can benefit both uniform and non-uniform networks. We develop a greedy load-balancing spare capacity reallocation (GLB-SCR) heuristic algorithm to implement this approach. Our experimental results show that GLB-SCR outperforms a previously proposed algorithm (SSR) in terms of established connection capacity and total network capacity in both uniform and non-uniform networks.