超立方体互连网络中的组播算法研究

在高性能计算中,涉及全局数据迁移、进程控制等操作的通信被称为聚合通信。高效的聚合通信服务不仅能够简化编程,而且能够提高系统效率和整体性能。组播作为聚合通信的通用模式之一,长期以来都是人们的研究重点,包括硬件加速、软件优化、针对不同拓扑结构的研究等。本文研究了超立方体网络中的组播算法,并分析了进一步的研究方向。     

互连网络局部迭代负载平衡技术

新的基于网络的计算模式（如网格计算,云计算,P2P计算）的共同特点是计算节点之间都是通过互连网络进行通信。对互连网络各个计算节点产生的工作负载进行平衡是提高计算系统性能的关键。文章介绍了近年来在互连网络上使用局部迭代方式求解负载平衡问题在算法设计及其性能分析反面的若干基本研究成果。     

Interconnection Networks

Interconnection networks are a natural result of advances in computer technology that brought about demands for improved system performance. As computer systems evolved from the batch-processing models of the 1960's to the time-sharing models of the 1970's, their evolution was basically confined within the von Neumann architectural model, with hardware costs being a significant limiting factor. However, contemporary IC technology is creating an entirely new atmosphere; it is now economically feasible to construct a multiple-processor computer system by interconnecting a large number of off-the-shelf processor and memory modules. In addition, because of today's increased performance requirements, the number of functional modules (homogeneous or heterogeneous) in the multiple-processor system normally keeps rising as the domain of applications grows. Trying to counter this trend presents quite a challenge to computer architects.     

Interconnection Networks Using Shuffles

Networking techniques allow several processors within a multiprocessing system to cooperate efficiently on a single large problem.     

A Kind of Multistage Interconnection Networks with Multiple Paths

1ThisworkwassupportedbytheNationalNaturalScienceFoundationofChina,GralltNo.69473024.1IntroductionMultiprocessorsystemsoftenuseinterconnectionnetworkstoconnectproces-sorsormemorymodules-Atime-sharedbusisthesimplestformofinterconnectionnetworks,butitcannotprovidetheperformancerequiredinmultiprocessorsystemstoday.Acrossbarswitchnetworkisanalternativeusedintheearliersystemstoimplementinterconnection.Theonlydelaytoconnectinputstooutputsisthatofasingleswitchinggate,butacrossbarswitchnetworkisver…     

A Kind of Multistage Interconnection Networks with Multiple Paths

Mltistage Interconnection Networks(MINs)are orten used to provide interconnections in multiprocessor systems.A unique path MIN usually has lower hardware complexity and a simple control algorithm,but it lacks fault tolerance.This paper proposes a kind of multipat MINs,which are obtained by adding auxiliary links at the final stage in Quad Tree(QT) networks so that they can provide more paths between each source-destination pair,and presents their routing algorithm which is both destination tag based and adaptive.Starting with the routing tag for the minimum path between a given source-destination pair,the routing algorithm uses a set of rules to select switches and modify routing tag.In addition to trying the auxiliary link when link0 an link1 are unavilable,link1 will be tried when link0 ys unavailable.This feature distinguishing the proposed routing algorithm form that for QT networks makes better use of all the possible paths between the given source-destination pair.In the end,this paper introduces a performance index,which is called capacity,to compare different kinds of MINs .Comparison shows that the proposed MINs have better capacity than QT networks.     

Interconnection Networks for SIMD Machines

Many SIMD interconnection networks have been proposed. To put the different approaches into perspective, this analysis compares a number of single- and multistage networks.     

基于SBC的SIP网络互通的研究

本文讨论了在Firewall和NAT环境下,部署大范围基于SIP的语音和多媒体业务的过程中引发的问题,并就如何在保证用户安全性不受影响的前提下为位于防火墙(Firewall)和网络地址转换(NAT,Network Address Translation)设备之后的终端用户提供业务接入问题进行了研究.然后引出并详细介绍基于会话边界控制(Session Border Control)的SIP多媒体网络安全互通的解决方案,具有较高的实用价值.     

Intermittent Fault Diagnosability of Interconnection Networks

An interconnection network’s diagnosability is an important metric for measuring its self-diagnostic capability. Permanent fault and intermittent fault are two different fault models that exist in an interconnection network. In this paper, we focus on the problem pertaining to the diagnosability of interconnection networks in an intermittent fault situation. First, we study a class of interconnection networks called crisp three-cycle networks, in which the cn _in -number (the number of common vertices each pair of vertices share) is no more than one. Necessary and sufficient conditions are derived for the diagnosability of crisp three-cycle networks under the PMC (Preparata, Metze, and Chien) model. A simple check can show that many well-known interconnection networks are crisp three-cycle networks. Second, we prove that an interconnection network S is a t _i -fault diagnosable system without repair if and only if its minimum in-degree is greater than t _i under the BGM (Barsi, Grandoni, and Masetrini) model. Finally, we extend the necessary and sufficient conditions to determine whether an interconnection network S is t _i -fault diagnosable without repair under the MM (Maeng and Malek) model from the permanent fault situation to the intermittent fault situation.     

COSI: A Framework for the Design of Interconnection Networks

Editor's note:This article presents a software framework for communication infrastructure synthesis of distributed systems, which is critical for overall system performance in communication-based design. Particular emphasis is given to on-chip interconnect synthesis of multicore designs.—Radu Marculescu, Carnegie Mellon University     

系统互连网络的容错策略研究

本文研究了互连网路由算法的容错问题,分析了各种切换技术下多种容错路由和错误恢复策略的特点及适用情况,研究了典型算法的优缺点。     

A Genetic Algorithm for Finding the Pagenumber of Interconnection Networks

A “book-embedding” of a graph G comprises embedding the graph's nodes along the spine of a book and embedding the edges on the pages so that the edges embedded on the same page do not intersect. This is also referred to as the page model. The “pagenumber” of a graph is the thickness of the smallest (in number of pages) book into which G can be embedded. The problem has been studied only for some specific kind of graphs. The pagenumber problem is known to be NP-complete, even if the order of nodes on the spine is fixed. Using genetic algorithms, we describe the first algorithm for solving the pagenumber problem that can be applied on arbitrary graphs. Experimental results for several kinds of graphs are obtained. We were particularly interested in graphs that correspond to some well-known interconnection networks (such as hypercubes and meshes). We also introduced and experimented with 2-D pagenumber model for embedding graphs.     

Multicasting in Generalized Multistage Interconnection Networks

Multistage interconnection networks (MIN) are popular in switching and communication applications. It is also well known as a hypercube derived architecture, offering a fixed-degree alternative to hypercube for a large class of applications. Message routing strategy in MIN is well known, however, multicasting issues for MIN has not been considered. This paper formulates the multicasting problem for MIN. We demonstrate that reordering the dimensions in MIN can lead to traffic reduced multicasting. This leads to the formulation of optimality criteria in MIN multicast operation. Traffic optimum multicasting in MIN is shown as a NP-Complete problem. We present a polynomial time greedy heuristic to generate traffic reduced multicast in MIN. The greedy approach generates a locally optimum solution. Analytical study and simulation results are presented showing the traffic reduction that can be obtained using our approach over traditional linearly ordered dimensions approach.     

Research Challenges for On-Chip Interconnection Networks

On-chip interconnection networks are rapidly becoming a key enabling technology for commodity multicore processors and SoCs common in consumer embedded systems, the National Science Foundation initiated a workshop that addressed upcoming research issues in OCIN technology, design, and implementation and set a direction for researchers in the field.     

LHL-立方体互连网络及其性质

并行计算系统一直是计算机科学中的重要研究领域,其互连网络的拓扑性质对整个网络的性能起着非常重要的作用.目前已经提出多种互连网络,其中超立方体具有对数级的直径、高连通度、对称性等很好的性质,故被用作多种并行机的处理器连接的拓扑结构.然而,超立方体并非所有性质都是最优的互连网络,且超立方体的许多变型结构具有许多比超立方体更好的性质,其中已经证明了局部扭立方体在直径、Hamilton连通性等方面都优于超立方体.给出在超立方体与局部扭立方体的顶点间的一种连接方式--超连接,从而得到一种称为LHL-立方体的新型网络,并对这种网络的以下性质进行了研究:顶点连通度、边连通度、Hamilton连通性、直径.研究结果表明,一个n维LHL-立方体是一个具有2n个顶点和n2n-1条边的n-正则图,n维LHL-立方体的顶点连通度和边连通度均为n,且是Hamilton连通的,直径上界为[n/2 ]+3.     

几类新的笛卡尔乘积互连网络

Star网络、Pancake网络、Bubble sort网络、修正Bubble sort网络(又称圈图)、轮图等都既是Cayley图又是重要的互连网络。利用图的笛卡尔乘积方法构建了几类新的笛卡尔乘积互连网络:环网、循环移数网络、ILLIAC网络、超立方体分别与Star网络、Pancake网络、Bubble sort网络、修正Bubble sort网络、轮图的笛卡尔乘积网络;这些网络的某些性能指标(例如,直径等)比Star网络或超立方体更好。     

BC互连网络及其性质

提出一种称为一一对应连接（BC）图的互连网络族，使其包含超立方体、交叉立方体和Mobius立方体作为基具子集，同时又使其具有与超立方体、交叉立立体和Mobius立方体相同的对数级的直径和顶点度数、最高连通（容错）度和相同的可诊断性等性质，从而使对超立方体及与其结构相似的大量互连网络的某些性质的研究合而为一，证明了BC互连网络族中包含一类Hamilton连通图并给出了BC互连网族中的图的直径的一个猜想。