基于粒子群和博弈论的QoS组播路由算法

为改善互联网的服务质量(QoS)组播路由能力,设计一种基于多子群和博弈论的QoS组播路由算法。该算法由边评判、博弈分析和组播路由树建立等部分组成。基于适合隶属度函数对边进行模糊综合评判,利用博弈分析方法确定网络提供方与用户在边上的效用Nash均衡程度,通过组播路由树建立算法,在用户QoS要求得到满足的条件下,使得网络提供方效用与用户效用达到或接近Nash均衡意义下的Pareto最优。仿真实验验证了该算法的良好性能。     

基于模糊积分和博弈论的QoS组播路由机制

下一代互联网NGI(next generation Intemet)需要提供服务质量QoS(quality of service)路由能力.由于NGI网络状态难以精确测量与表达,因此,QoS路由基于的信息应该是模糊的.随着网络运营的渐趋商业化,付费上网要求实现QoS计费,而网络提供方与用户的利益冲突要求实现效用双赢.设计了一种基于模糊积分和博弈论的QoS组播路由机制.该机制由边评判、博弈分析和组播路由树建立算法组成,基于模糊积分和适合隶属度函数对边进行模糊综合评判,通过博弈分析确定网络提供方与用户在边上的效用能否达到Nash均衡,通过组播路由树建立算法使得在建立的组播路由树上不仅用户QoS要求得到满足,而且网络提供方效用与用户效用达到或接近Nash均衡下的Pareto最优.仿真结果表明,与QoSMIC等机制相比,该机制具有较好的性能.     

一种基于故障时间的可调域间出口选择算法

在大型Internet服务提供商中,BGP (border gateway protocol)出口路径选择常常采用"热土豆"机制.然而研究表明,该机制具有相当大的局限性以及出口调节的间接性,它容易影响域间路由的健壮性.针对"热土豆"机制的缺点,出现了一些新的BGP出口路径选择机制和算法.然而,这些方法在解决问题时往往忽略网络运行过程中经常出现的IP链路故障或故障持续时间的影响.提出了一种基于故障时间的可调域间出口路径选择算法,该算法能够根据流量工程的目标、路由稳定性等要求进行动态的调整,同时满足路由变化的实时性.模拟实验结果表明,该算法能够有效地在多个目标之间达到平衡.     

无线Mesh网络中多信道生成树路由算法

无线Mesh网络是一种特殊的AdHoc网络。它易于部署、安装,能有效地构建无线骨干网,通常被用作宽带Internet接入和扩展无线LAN的覆盖范围。针对无线Mesh网络的特点,提出了一种不同于一般MANET路由协议的路由算法。该算法基于网络拓扑生成树,使用多个无重叠信道;在解决信道分配问题的同时,兼顾信道多样性和信道重用,更好地利用无线频谱资源,支持链路并行传输。     

Convergence routing on disjoint spanning trees

This paper presents a new design and a performance study for convergence routing in a general network with multiple spanning trees. Such an arbitrary topology network is used in the design of a switch-based LAN/MAN architecture. Convergence routing can be viewed as a variant of deflection routing which combines, in a dynamic fashion, the on-line routing decision with the traffic load inside network. However, unlike other deflection techniques, convergence routing guarantees that packets will reach (or converge) to their destinations.In particular, a new algorithm for constructing two edge-disjoint spanning trees of a given network is presented, and the resulting trees are used for convergence routing. It is shown empirically that convergence routing on two edge-disjoint spanning trees yields a better bound than a single spanning tree, on the maximum route length. The construction of the two edge-disjoint spanning trees is done with specific strategies for improving the fault-tolerance and performance of the system.     

一种新的低压电力线网络路由器设计

低压配电网络具有物理拓扑未知和信道时变性等特征,通信可靠性问题严重制约了其在实际应用的规模。论文通过对现有电力线载波通信网络结构的分析比较,提出了适用于低压电力线窄带载波通信的树簇路由算法。首先建立树簇路由算法的协议框架,然后设计了簇生成、簇维护、骨干树生成和树维护等模块算法。最后给出了树簇路由实现策略。分析表明,树簇结合的动态路由满足了低压窄带载波通信技术条件。     

云环境下利用用户到数据中心建模的高效节能路由算法

针对云计算用户、服务、供应商和数据中心的密度不断增长导致传输数据、网络流量和基础设施的大量能耗问题,提出针对云数据的高效节能路由算法。其目的是在用户和数据中心之间定位出最低能量消耗路线,同时确保用户需求。首先,对用户到数据中心的连通性进行建模,分析了网络拓扑结构;然后为了用户意图最简化和能量最小化,通过遍历节点最小数的基线最短路径算法进行评估,将用户任务通过最节能路径发送到数据中心,从而最小化能量损耗和服务响应时间(SRT)。实验的网络拓扑结构使用互联网服务提供商(ISP)的分支设计。实验结果表明提出的算法具有更短的路由路径长度和更低的路由能耗。此外,最短路径方法只有在成功发送或接收之后才能确定最节能的路由。     

使用蚁群优化的WMSNs负载均衡路由方案

由于无线多媒体传感器网络（WMSNs）具有资源受限、信道容量可变、数据冗余度高等特点,研究WMSNs的QoS 路由具有极大的挑战性。针对上述问题,提出了一种使用蚁群优化的WMSNs负载均衡路由方案——ACOLBR。ACOLBR采用分簇技术进行区域划分,簇间利用ACO找到一条簇首到基站的最优路径,簇内利用以簇首为根节点的最小生成树算法组织路由。仿真结果表明,与AGRA和M-IAR算法相比,ACOLBR在负载均衡、传输时延、传输成功率、可扩展性和自适应性等方面均有较大改进,实现了全网的负载均衡,有效地延长了网络生命期,保证了网络传输的QoS。     

HURP/HURBA: Zero-configuration hierarchical Up/Down routing and bridging architecture for Ethernet backbones and campus networks

Ethernet switched networks do not scale appropriately due to limitations inherent to the spanning tree protocol. Ethernet architectures based on routing over a virtual topology in which turns are prohibited offer improved performance over spanning tree, although in some cases suffer from excessive computational complexity. Up/Down routing is a turn prohibition algorithm with low computational complexity. In this paper we propose HURBA, a new layer-two architecture that improves Up/Down routing performance due to an optimization based on the use of hierarchical addressing, while preserving the computational complexity of Up/Down. The resulting architecture requires zero-configuration, uses the same frame format as Ethernet, allows upgrades by software update, and is compatible with 802.1D bridges by means of encapsulation. HURP protocol builds automatically a core with the interconnected HURP routing bridges and the standard bridges get connected to the edges in standard spanning trees. Simulations show that the performance of HURP, evaluated over various combinations of network topology and size, is close to the one of shortest path, is consistently better than that of Up/Down, and is equal or better than Turn Prohibition, with the advantage of having a lower complexity.     

一种基于最小生成树的非均匀分簇路由算法

分簇式路由是无线传感器网络路由协议研究的重点,本文提出一种新的基于最小生成树的非均匀分簇路由算法,该算法利用EECS路由协议产生大小非均匀的簇,簇内结点通过单跳的方式将数据发送给簇首结点,所有簇首结点构成最小生成树路由网络,并通过树内结点的多跳通信,最终将数据发送给sink结点.实验证明,本文算法与EECS相比能够更加有效地降低整个网络的能量消耗,延长网络的生命周期.     

A general methodology for direction-based irregular routing algorithms

This paper presents a general methodology for generating deadlock-free routing algorithms for irregular networks. Constructing a spanning tree on the given network, assigning directions to the network channels, creating deadlock-free zones, and specifying a logical sequence of the produced deadlock-free zones are the four fundamental steps that the proposed methodology takes to generate deadlock-free and connected routing algorithms. By applying the proposed methodology with two known labeling methods we have generated six irregular routing algorithms: three of them are novel routing algorithms and three of them (the Up/Down, Left/Right, and L-turn routing algorithms) have already been proposed in the literature. Extensive simulation experiments have been performed considering various network topologies, different network sizes (considering different network nodes and network channels), various message lengths, a variety of spanning tree roots, and a wide range of message (traffic) generation rates. Simulation results show that the six routing algorithms can be divided into three pairs. Routing members of each pair show similar behavior in terms of message latencies and saturation generation rates. However, it is worth noting that for a given topology the performance of the six routing algorithms may be totally different and it mainly depends on the network topology.     

Distributed hierarchical search for balanced energy consumption routing spanning trees in wireless sensor networks

We provide a new heuristic method approach to search for degree-balanced and small weight routing spanning trees in a network. The method is a modification of Kruskal’s minimum spanning tree search algorithm and is based on a distributed search by hierarchical clusters. It provides spanning trees with a lower maximum weighted degree, a bigger diameter, and can be used for balanced energy consumption routing in wireless sensor networks (WSN’s). The method can be naturally implemented in parallel or as a simple locally distributed algorithm. Simulations for a realistic case scenario WSN are done based on the transmission energy matrix. The simulation results show that the proposed approach can extend the functional lifetime of a WSN in terms of sensor transmission energy by 3–4 times. We also show that the results can be further improved by using a preliminary clustering of the input network.     

一种基于支撑树搜索的多下一跳路由算法*

基于通过搜索支撑树定势的思想,提出了一种新型多下一跳路由算法,具体包括四种可行的实现方案。该算法选路策略灵活,通过计算网络拓扑的支撑树完成对节点的定势,可以产生到目的地的大量路径同时进行分流传输,充分利用网络资源。仿真结果表明,相对于传统单下一跳路由算法,该算法能有效地提高吞吐量,减小丢包率,提升网络整体通信性能。     

多QoS约束的层次多播路由算法框架

为了解决网络路由的扩展性问题。大型网络通常被划分成若干个不同的域。拓扑聚集是对这些域的拓扑状态信息进行汇总的过程。在拓扑聚集的基础上,QoS层次多播路由算法用来构造满足QoS要求的域闻多播树。现有的QoS层次多播路由算法在其拓扑聚集和路径计算的过程中都只考虑了存在两个QoS特征值的情况。本文提出了一种具有多QoS约束的层次多播路由算法框架HMRMQ（Hierarchical Multicast Routing with Multiple QoS constraints）,此算法框架不仅为基于多QoS特征值的拓扑状态聚集和状态信息表示提供了新的方法,而且提出了一种适应于多QoS约束的层次多播路由新算法。我们提出的状态信息表示法和拓扑聚集算法都具有很好的扩展性,分布式的路由算法也便于某些安全性策略的实施。理论分析和实验结果不仅证明了HMRMQ的正确性和有效性,同时也表明了HMRMQ在网络路由的扩展性、路由成功率、网络代价以及报文负载等方面都具有良好的性能。     

基于图论生成树的低压电力线通信路由方法

电力线信道的阻抗特性、信号衰减特性及噪声特性导致电力线通信的可靠性成为制约其广泛应用的重要因素。分析了低压配电网的物理拓扑结构和逻辑拓扑结构,结合我国低压集中抄表系统应用的工程特点,提出了一种基于图论生成树的电力线通信自动路由方法。该方法能够有效地建立起电力线通信网络路由,并根据信道变化动态地维护路由,保证了电力线网络的可靠性。实验测试表明了该路由方法的有效性、可靠性和实用性。     

NGI中一种基于食物链算法的柔性QoS组播路由算法

针对下一代互联网（Next Generation Internet,NGI）难以精确测量和用户服务质量（Quality of Service,QoS）需求难以完全表达的特点,设计了一种基于食物链算法（Food Chain Algorithm,FCA）的柔性QoS组播路由算法。给出了QoS组播路由问题模型及其数学描述,针对NGI中QoS参数信息不精确和用户需求柔性的特点,通过博弈分析确定用户和网络方在边上的效用能否达到Nash均衡,基于模糊数学的相关知识并结合FCA的寻优能力,找出在给定条件下用户效用、网络方效用和满足用户QoS需求的可信度同时达到最大的组播路由树。对算法进行了仿真实现与性能评价,结果表明,它是可行和有效的。     

Multi-robot navigation based QoS routing in self-organizing networks

The technical development drives the future networks to become large-scale, heterogeneous, and dynamic. Bio-inspired networking can help reduce the time-space complexity of the complex network. Due to the good features such as self-organization and self-management, self-organizing network (SON) will most probably be a priority choice for the next generation network. In this paper, a swarm intelligence based Quality of Service (QoS) routing protocol is proposed for SON. The inaccurate routing and QoS information is described with fuzzy mathematics whilst the utilities of both the user and the network service provider are considered by applying game theory. Based on the multi-robot navigation algorithm, the protocol is able to search a routing path which can satisfy the user QoS requirements and achieve the Pareto optimal utilities of the user and the network service provider under Nash equilibrium. The proposed protocol is implemented and evaluated by extensive simulation experiments. The results show that it beats both other swarm intelligence based routing protocols and the traditional Dijkstra algorithm based routing protocol. The searched routing paths support the win–win effect for both the user and the network service provider.     

Experimental validation of resilient tree-based greedy geometric routing

Geometric routing is an alternative for IP routing based on longest prefix matching. Using this routing paradigm, every node in the network is assigned a coordinate and packets are forwarded towards their intended destination following a distance-decreasing policy (greedy forwarding). This approach makes the routers significantly more memory-efficient compared to the current IP routers. In this routing, greedy embeddings are used to guarantee a 100% successful delivery to every destination in the network. Most of the existing proposals lack resiliency mechanisms to react efficiently to network changes. We propose a distributed algorithm to calculate a greedy embedding based on a spanning tree of the network. In this algorithm, nodes are triggered to re-calculate their coordinates upon a change in the topology such as link or node failures. The advantage of this approach is that it recovers from topology failures within a very short period of time. We further extend the algorithm to generate backups to apply protection in distributed setups. Different trade-offs and trends of re-convergence for geometric routing have been evaluated in an emulation environment. Realistic results are achieved through emulation as no model or abstraction is involved. The proposed routing scheme is implemented in Quagga routing software and new elements are developed in Click modular router to enable greedy forwarding. For the first time, the performance of this scheme is evaluated through emulation on a large topology of 1000 nodes and the results are compared with BGP. The experimental results indicate that the proposed scheme has interesting characteristics in terms of convergence time upon a change in the network topology.     

一类新的层次双环网络及其最优路由算法

用图的笛卡尔积Fm×Fm-1×…×F1×G构造一类新的层次双环网络,给出其最优路由算法。图G为Petersen图,Fi为特殊的无向双环网络。研究网络的一些基本性质,并与杜艳等构造的层次双环网络(计算机工程与应用,2010年,第34期)进行比较。分析结果表明,新构造的网络是一类接连度小、直径短,存在简单且路由算法最优的新型网络拓扑结构。     

基于源区域路径选择的层次化片上网络路由算法

针对较大规模片上网络(NoC)远端节点和邻近节点之间的通信问题,提出一种基于区域划分的层次化簇状分层网（CHM）结构。在此基础上,针对中间节点拥塞严重导致网络性能降低的问题,提出一种基于源区域路径选择的自适应算法。该算法利用CHM结构区域特性将路由决策由源节点移至源区域,同时在原有底层和上层节点对的基础上增加自适应节点对,并增加该部分节点对路由选择性,从而缓解网络拥塞状况。仿真实验表明,与最短路径算法相比,在合成流量和局部化流量模式下,该算法下的CHM结构饱和注入率最多可分别提升约51%和31%,因此该算法可有效提升网络整体吞吐性能。