Abstract The goal of the ShanghaiGrid is to provide information services to the people. It aims to construct a metropolitan‐area information service infrastructure and establish an open standard for widespread upper‐layer applications from both communities and the government. The Information Service Grid Toolkit and a typical application called the Traffic Information Grid are discussed in detail. Copyright © 2005 John Wiley & Sons, Ltd.

Multistage interconnection networks (MINs) are a popular class of switch-based network architectures for constructing scalable parallel computers. Four wormhole MINs built from k/spl times/k switches, where k=2/sup i/ for some j, are considered in this paper: traditional MINs (TMINs), dilated MINs (DMINs), MINs with virtual channels (VMINs), and bidirectional MINs (BMINs). The first three MINs are unidirectional networks, and we show that the cube interconnection pattern can provide contention-free and channel-balanced partitioning of binary cube clusters. BMINs based on butterfly interconnection are essentially a fat tree, and their routing properties are described. Performance comparison among these four networks using simulation experiments is presented with respect to different network traffic patterns. Both DMINs (dilation two) and BMINs have a similar hardware complexity. We conclude that a two-dilated MIN outperforms the corresponding BMIN (or fat tree) for most of the traffic conditions and is a better choice for the design of scalable parallel computers.

Multistage interconnection networks are a popular class of interconnection architecture for constructing scalable parallel computers (SPCs). The focus of this paper is on the multistage network system which supports wormhole routed turnaround routing. Existing machines characterized by such a system model include the IBM SP-1 and SP-2, TMC CM-5, and Meiko CS-2. Efficient collective communication among processor nodes is critical to the performance of SPCs. A system-level multicast service, in which the same message is delivered from a source node to an arbitrary number of destination nodes, is fundamental in supporting collective communication primitives including the application-level broadcast, reduction, and barrier synchronization. This paper addresses how to efficiently implement multicast services in wormhole-routed multistage networks, in the absence of hardware multicast support, by exploiting the properties of the turnaround switching technology. An optimal multicast algorithm is proposed. The results of implementations on a 64-node SP-1 show that the proposed algorithm significantly outperforms the application-level broadcast primitives provided by currently existing collective communication libraries including the public domain MPI.

Multistage interconnection networks are a popular class of interconnection architecture for constructing scalable parallel computers (SPCs). The focus of the paper is on wormhole routed multistage networks supporting turnaround routing. Existing machines characterized by such a system model include the IBM SP-1, TMC CM-5, and Meiko CS-2. Efficient collective communication among processor nodes is critical to the performance of SPCs. A system level multicast service, in which the same message is delivered from a source node to an arbitrary number of destination nodes, is fundamental in supporting collective communication primitives including the application level broadcast, reduction, and barrier synchronization. The paper addresses how to efficiently implement multicast services in wormhole routed multistage networks, in the absence of hardware multicast support, by exploiting the properties of the switching technology. An optimal multicast algorithm is proposed. The results of implementations on a 64-node SP-1 show that the proposed algorithm significantly outperforms the application level broadcast primitives provided by currently existing collective communication libraries including the public domain MPI.>