一种面向应用的NoC容错路由算法

随着芯片集成度的不断提高,芯片制造工艺进入深亚微米级以后,片上将会出现更多难以预测与消除的故障类型。为了实现可靠的片上通信,应用容错机制与算法是一个重要的解决方案。本文提出一种面向应用的NoC容错路由算法,该算法在重负载时使用带有部分故障的链路并使流量在网络中均匀分布。同时给出了实现该算法需要的扩展后的路由器结构。仿真结果表明,所提出的路由算法与现有的路由算法相比,具有更好的时延性能。     

基于NoC的容错路由算法

各种各样的软件和硬件上的错误都会破坏网络的数据传输,因此研究No C网络的容错算法是非常必要的。在基于XY路由算法的基础上提出了改进的容错路由算法,当链路或者传输节点之间发生错误时,可通过重新设置路由规则来获取一条有效的路由路径。在FPGA上进行路由容错算法的仿真,并和目前常用的几种路由算法在所适用拓扑、是否防止死锁等方面进行对比。仿真结果显示改进的路由容错算法性能优越,是可行的。     

多域光网络联合路由保护算法

研究了多域光网络中的路由保护问题。为了避免多域光网络通路保护二步算法可能导致的多域陷阱问题,提出了一种基于Suurballe算法扩展的多域联合路由保护算法。仿真表明,相比传统的多域通路保护二步算法,该算法资源利用率高,阻塞率低,平均每连接跨域数小。     

超立方体网络中基于局部安全信息的广播容错路由研究

针对具有错误节点和故障链路的超立方体网络,改进了一种算法实现可靠的容错广播路由。在没有安全结点的不安全的超立方体网络中,将网络分成一系列最大安全子立方体,根据提出的故障链路处理方法和选择广播路由的准则,改进了基于局部安全信息的广播路由算法。证明了根据文中算法,这些最大安全子立方体在满足文中要求的情况下,仍有可能实现可靠的广播路由,有效地提高了信息路由的可靠性。提供了实例介绍文中算法的原理和优点。     

面向Ad Hoc网络的多路径路由协议研究

Ad Hoc网络多路径路由协议作为对单路径的扩展,具备提供容错、负载平衡和更多的聚合带宽等优点。本文在研究了一种典型路由协议的基础上,提出了一种基于变化能量的多路径路由协议算法。仿真实验表明,该改进算法相对于AODV协议在时间延迟和成功投包率上都得到了较大的提高。     

面向能量感知的DTN地理位置路由算法在灾害地域的应用

延迟容错网络中的路由特点是不存在一条端到端的通路.这种特征可用于基础设施被摧毁的灾害地区.使用现有的移动平台如手机,建立一个能源感知的通信网络是一个有吸引力的问题.本文基于预测的路由和传输控制机制,提出了一种地理位置的协议.通过使用雅安地区的实际地图作为实验地图,对比现有的经典协议,可以发现该算法增加了消息投递成功率,降低了传输延时,并大大降低了路由开销.此外,算法的消息传输跳数比其他算法更接近于传染病路由算法.     

2—连通图上构成最优容错路由选择一种新方法

图Ｇ和路由选择ρ对故障集Ｆ的容错性能可从其幸存路由图的直径的大小得到反映。本文给出了构成路由选择ρ的一种新方法，此方法对任一２－连通图Ｇ的任一故障ｆ，在实现ρ为最优容错路由选择的同时，弥补了现有最优容错路由选择中不能将各边都选择为其２端点之间的路由的不足。     

接口标记容错路由算法

随着片上系统(SoC)集成度的不断提高,IP核之间的通信故障成为亟待解决的问题,片上网络(NoC)是解决SoC通信问题的有效途径。容错路由算法是NoC设计中的关键技术,对NoC的通信效率有重要影响。在Valiant随机路由算法和源路由算法的基础上,提出了一种接口标记容错路由算法。该算法吸取了Valiant随机路由算法能平衡网络负载、降低拥塞概率的优良性能与源路由算法中路径不需要计算与查找的特点,减小了传输时延,提高了路由器的利用率。     

仿血管路径的无线传感器网络故障容错路由算法

为提高无线传感器网络故障容错性和传输稳定性,实现网络负载均衡,提出了一种仿血管路径的无线传感器网络故障容错路由算法.研究了人体血管路径特性及属性关联,对网络节点分区域等级标定并以不同概率值进行静态分簇,运用改进的蚁群算法BWAS(最优最差蚂蚁系统)生成节点路径,以路径信息素值作为传输路径的选择概率建立仿血管拓扑结构路由...     

k元n立方并行容错路由

本文讨论了k元n立方并行容错路由问题,给出了k元n立方并行容错路由并行条数的一个下界,也给出每条路径步长的一个下界,证明过程同时也可转化为求并行路径的算法。     

Embedded unidirectional incomplete hypercubes for optical networks

Many proposals of virtual regular topologies embedded in physical topologies for high-speed wavelength division multiplexing (WDM) optical networks do not consider the issue of allowing a variable number of nodes in the network. A solution for embedding a virtual unidirectional incomplete hypercube into a physical topology that does is presented. The proposed solution is a multichannel multihop network which has several elegant features: (a) it allows any number of nodes to be connected to the network, (b) it only requires a minor effort to reconfigure the new interconnection whenever a node is added or deleted for the network, (c) it supports a self-routing strategy, (d) the aggregate throughput of the network increases as more nodes are added, and (e) alternate paths are available which have a comparable distance to the destination as the primary path. The performance of the scheme is comparable to the performance of both the unidirectional hypercube and the bidirectional hypercube     

A fault tolerant routing scheme for hypercubes

An efficient distributed fault‐tolerant routing algorithm for the hypercube is proposed based on the existence of a complete set of node‐disjoint paths between any two nodes. Node failure and repairs may occur dynamically provided that the total number of faulty nodes at any time is less than the node‐connectivity n of the n‐cube. Each node maintains for each possible destination which of the associated node‐disjoint paths to use. When a message is blocked by a node failure, the source node is warned and requested to switch to a different node‐disjoint path. The methods used to identify the paths, to propagate node failure information to source nodes, and to switch from one routing path to another incur little communication and computation overhead. We show that if the faults occur reasonably apart in time, then all messages will be routed on optimal or near optimal paths. In the unlikely case where many faults occur in a short period, the algorithm still delivers all messages but via possibly longer paths. An extension of the obtained algorithm to handle link failures in addition to node failures is discussed. We also show how to adapt the algorithm to n‐ary n‐cube networks. The algorithm can be similarly adapted to any interconnection network for which there exists a simple characterization of node‐disjoint paths between its nodes. This revised version was published online in June 2006 with corrections to the Cover Date.     

基于重要度传输矩阵的复杂网络节点重要性辨识方法

复杂网络中节点重要性辨识对分析网络结构和功能具有重要作用.为了辨识节点重要性,分析节点自身和关联节点的作用,本文构建了一种基于重要度传输矩阵的节点重要性辨识模型.首先,基于关联节点与节点之间的最优路径长度、最优路径数目和信息传播率定义了节点间的传输能力.其次,依据度值和传输能力构建重要度传输矩阵,综合节点局部重要性和全局属性指标评价节点的重要性.最后,对"ARPA"网络和四个真实网络进行破坏性仿真分析,结果本文方法表明对网络造成更大的破坏,证明了该方法的有效性和可靠性.     

Reliable broadcasting in wormhole-routed hypercube-connected networks using local safety information

This paper presents a method to cope with reliable broadcasting in faulty hypercubes using local safety information. A new definition, broadcast subcube, is introduced, with which various techniques are proposed to improve performance of the broadcast algorithm. Local safety information is well used in the fault-tolerant broadcast algorithm by considering only safety of the broadcast subcube. An unsafe hypercube can be split into a set of maximal safe subcubes. If these maximal safe subcubes meet certain requirements (listed in this paper), then broadcasting can still be done successfully and, in some cases, optimal broadcast is still possible. The sufficient condition for optimal broadcast of a message is presented in an unsafe hypercube. Extensive simulation results show that the proposed method outperforms previous methods, in all cases.     

Detection of Wormhole Attack and Secure Path Selection in Wireless Sensor Network

In Wireless Sensor Network (WSN), securable data transmission is one of the most challenges. During the transmission between the source and a destination node, routing information of the particular path may be misbehaved by the particular nodes which are known as wormhole nodes/attackers. The paths which include the wormhole nodes are known as wormhole attacked paths. For improving security in WSN, these wormhole attacked paths should be identified. To achieve this, wormhole attack detection method and optimal or secure path selection are presented in this paper. Initially, ‘K’ paths or multiple paths are generated between source and destination using Ad-hoc On demand Multipath Distance Vector (AOMDV) routing protocol. Then, the source node identifies the wormhole attacked path by verifying the Detection Packet (DP) and Feedback Packet (FP) from the destination. After detecting the wormhole attacked paths, the source node selects the optimal path among the attacker free paths using Particle Swarm Optimization (PSO) algorithm. Simulation results show that the performance of the proposed approach improves energy efficiency and network lifetime of the network.

     

Improved algorithms for computing with faulty SIMD hypercubes

Computation time for various primitive operations, such as broadcasting and global sum, can significantly increase when there are node failures in a hypercube. In this paper we develop nearly optimal algorithms for computing important basic problems on a faulty SIMD hypercube. In an SIMD hypercube, during a communication step, nodes can exchange information with their neighbors only across a specific dimension. Our parallel machine model is an n-dimensional SIMD hypercube Q _n with up to n-1 node faults. In an SIMD hypercube, during a communication step, nodes can exchange information with their neighbors only across a specific dimension. We use the concept of free dimension to develop our algorithms, where a free dimension is defined to be a dimension i such that at least one end node of any i-dimension link is nonfaulty. In an n-cube, with f < n faults, it is known that there exist n-f+1 free dimensions. Using free dimensions, we show that broadcasting and global sum can be performed in n+5 steps, thereby improving upon the previously known algorithms for these primitives. The broadcasting algorithms work independent of the location of source node and faulty nodes. This revised version was published online in June 2006 with corrections to the Cover Date.     

太比特路由器多元超立方体交换结构时延性能分析

在交换结构的设计中引入多元超立方体静态互连技术，本文提出了一种新的分布式多机架太比特级交换网络：多元超立方体交换结构(MHSF)和相关的汉明随机路由算法(MRRA)。理论分析表明，当各交换节点的流量均匀地发送到各个目的节点时，信元通过MHSF的平均时延有确定的上界。在一定的链路加速因子条件下，MHSF具有可接受的平均时延。     

E‐TDGO: An encrypted trust‐based dolphin glowworm optimization for secure routing in mobile ad hoc network

Mobile ad hoc networks (MANETs) are independent networks, where mobile nodes communicate with other nodes through wireless links by multihop transmission. Security is still an issue to be fixed in MANETs. Hence, a routing protocol named encrypted trust‐based dolphin glowworm optimization (DGO) (E‐TDGO) is designed using Advanced Encryption Standard‐128 (AES‐128) and trust‐based optimization model for secure routing in MANET. The proposed E‐TDGO protocol includes three phases, namely, k‐path discovery, optimal path selection, and communication. At first, k paths are discovered based on the distance and the trust level of the nodes. From the k paths discovered, the optimal path is selected using a novel algorithm, DGO, which is developed by combining glowworm swarm optimization (GSO) algorithm and dolphin echolocation algorithm (DEA). Once the optimal path is selected, communication begins in the network such that E‐TDGO protocol ensures security. The routing messages are encrypted using AES‐128 with shared code and key to offer security. The experimental results show that the proposed E‐TDGO could attain throughput of 0.11, delay of 0.01 second, packet drop of 0.44, and detection rate of 0.99, at the maximum number of rounds considered in the network of 75 nodes with attack consideration.     

Energy‐efficient multihop routing in WSN using the hybrid optimization algorithm

The technical growth in the field of the wireless sensor networks (WSNs) has resulted in the process of collecting and forwarding the massive data between the nodes, which was a major challenge to the WSNs as it is associated with greater energy loss and delay. This resulted in the establishment of a routing protocol for the optimal selection of the multipath to progress the routing in WSNs. This paper proposes an energy‐efficient routing in WSNs using the hybrid optimization algorithm, cat–salp swarm algorithm (C‐SSA), which chooses the optimal hops in progressing the routing. Initially, the cluster heads (CHs) are selected using the low‐energy adaptive clustering hierarchy (LEACH) protocol that minimizes the traffic in the network. The CHs are engaged in the multihop routing, and the selection of the optimal paths is based on the proposed hybrid optimization, which chooses the optimal hops based on the energy constraints, such as energy, delay, intercluster distance, intracluster distance, link lifetime, delay, and distance. The simulation results prove that the proposed routing protocol acquired minimal delay of 0.3165 with 50 nodes and two hops, maximal energy of 0.1521 with 50 nodes and three hops, maximal number of the alive nodes as 39 with 100 nodes and two hops, and average throughput of 0.9379 with 100 nodes and three hops.