FdSPICE: A parallel simulation technique for lossy and dispersive interconnect networks

A new and efficient technique is presented for modelling and simulation of interconnect networks which include multiconductor microstrip transmission lines (MMTL) with inhomogeneous cylindrical substrates. The potential and field distributions in the cross section of the MMTL are calculated by solving a set of series equations using Galerkin's method. The charge distribution on the conductors, maxwellian capacitance matrix per unit length, and the modal characteristic impedances of the MMTL are determined. Results obtained have been compared for various types of microstrip lines with those obtained in the literature; good agreement has been found.

Graph embedding has been known as a powerful tool for implementation of parallel algorithms and simulation of interconnection networks. In this paper, we introduce a technique to obtain a lower bound for the dilation of an embedding. Moreover, we give algorithms for embedding variants of hypercubes with dilation 2 proving that the lower bound obtained is sharp. Further, we compute the exact wirelength of embedding folded hypercubes and augmented cubes into hypercubes.

The use of conservative parallel simulation techniques to accelerate multistage interconnection network simulation is addressed. The conventional null-message approach to resolving the deadlock problem in conservative simulation may lead to a livelock if lookahead cannot be guaranteed. We propose a new deadlock/livelock free scheme using null messages, but without the presumed lookahead, to co-ordinate the parallel simulation. A flushing mechanism to address the combinatorial explosion of memory consumption due to such null messages is also discussed. Our analysis shows that the proposed flushing mechanism effectively reduces the memory consumption from exponential to linear. Different partitioning and transformation techniques are used to map the simulation program onto multiprocessor platforms. Both the empirical and analytical results show an exceptional phenomenon that a balanced simulation workload distribution may not necessarily translate into better run-time performance.

This paper describes the design and use of the interconnection network simulator (ICNS) framework. ICNS is a modular, object-oriented simulation system that has been developed to investigate performance issues in multiprocessor interconnection networks that exploit photonic technology in their design. We describe the ICNS infrastructure, present two distinct photonic interconnection networks that have been modeled using ICNS, and give performance results for each of these networks.

Fine-Grained Parallel and Distributed Spatial Stochastic Simulation of Biological Reactions

By increasing the number of processors and with the help of the large-scale interconnection networks built on processors, the advanced multiprocessor systems, obtain their superpower of computing. However, the large-scale interconnection networks are very significant to the performance of any multiprocessor systems, but it also makes multiprocessor systems difficult to diagnose and isolate faulty processors. That’s why the multiprocessor systems should have a better fault diagnosis ability to ensure its reliability, and the ability of fault diagnosis of a multiprocessor system is normally measured by its diagnosability. Lexicographic product is a common method to construct a large scale interconnection network, so studying the diagnosability of multiprocessor system generated by the lexicographic product of networks will be beneficial to the development of multiprocessor systems. In this paper, we use the extending stars to obtain the accurate value of the diagnosability of the interconnection networks constructed by lexicographic product of m-order paths with n-order cycles, and prove that the diagnosability of lexicographic product of network is better than the Cartesian product of networks in certain cases.

Due to the recent advances in hardware technology, especially in the advent of VLSI circuit technology, it is now feasible to build a large and very complex interconnection networks connecting tens of thousands of processing elements for an MPS capable of executing parallel algorithms. For example, the Connection Machine [143] contains as many as 216 processors. Thus, a systematic method is very necessary to design a topological structure for such very large scale interconnection networks.

An implementation of a conservative parallel simulator with deadlock avoidance is presented. Its performance when working with a realistic model of a message routing network is evaluated and contrasted against a sequential simulator. Different factors that improve the performance of the parallel simulation are discussed, focusing in the model under study and the available computer: a network of transputers. These factors are the load of the model being simulated, the grain size of the simulator and the simulator ability to exploit the lookahead property of the model. >

In this paper we show the difficulties encountered when performing full system simulation of a distributed memory parallel system. To illustrate the problem, we have chosen a workbench that evaluates the impact on application performance of some simple congestion-control mechanism that can be implemented in the interconnection network. Applications of choice are some of those included in the NAS parallel benchmarks. Running a full-system, execution-driven simulation that combines Simics with an interconnection network simulator, we observe some unexpected, negative interactions of overlapping congestion control techniques implemented at the network level and at the host level. Each MPI implementation uses a different protocol stack, and some of them work without TCP. We compare and contrast results obtained with MPICH, LA-MPI and LAM

This paper considers software tools and linguistic constructions of the network simulator TRIADNS. Nowadays network applications - especially in the area of wireless networks - are becoming more and more complex which makes the design and the testing almost impossible without appropriate software. This software available to aid the user in simulating previously designed scenarios, scalable algorithms and changing structure of computer network. So it is necessary to have effective and flexible program tools for computer network design and simulation. Network simulator must design and investigate not only hardware, but software too, explore computer networks, considering in particular the specific characteristics of a variety of computer networks. Besides computer networks may include a lot of nodes. This paper discusses approaches allowing to decide the problems mentioned above: hierarchical model, using ontologies and Data Mining methods for the analyses of simulation results, using several computing nodes for computer network simulation (distributed and parallel simulation).

The implementation of parallel algorithms and the simulation of interconnection networks can be modeled into a graph embedding problem. Several cost parameters are used to assess the quality of an embedding. The wirelength is one of these factors that is frequently taken into account. A fractal cubic network is a new variant of the hypercube graph. In this study, we compute the wirelength of an embedding of the hypercube [Formula: see text] into the fractal cubic network [Formula: see text] using [Formula: see text]-partition.

Simulation of spiking neural networks — architectures and implementations

To derive the exact reliability expressions for large Multi-stage Interconnection Networks (MINs) can become rather complex. As network size increases, the reliability bounds could be used to estimate the reliability of the networks. In this paper, terminal, broadcast, lower and upper bounds network reliability will be determined. Lower bound reliability is the minimum probability that the system will be operational for a specified time. Upper bound reliability presents an optimistic view of probability that the system will work at some specified time, which is not the center of attention in terms of reliability point of view. If the lower bound reliability provides sufficient assurance that the system will be operational at some specified time, then no further effort for obtaining the exact reliability expression is necessary. As examples, the derivation of terminal, broadcast, lower and upper bounds network reliability expressions of the extra-stage cube network will be demonstrated.

CAD tools and research in the area of reduced-ordermodeling of large linear interconnect networks have evolvedfrom merely finding a Pad' e approximation for the givennetwork transfer function to finding an approximate transferfunction that preserves such circuit-theoretic propertiesof the network as stability, passivity, and RLC synthesizability.In particular, preserving passivity guarantees thatthe reduced-order models will be well-behaved when embeddedback in the circuit where the interconnect networkoriginated. While stability can be ascertained by studyingthe poles of the reduced-order transfer function, passivitydepends on both the poles and zeros of the networkdriving-point impedance. In this paper, we present a novelmethod for studying the zeros of reduced-order transferfunctions and show how it yields conclusions about passivityand synthesizability. Moreover, in order to obtain aguaranteed-passive reduced-order model for multiport RCnetworks, a new algorithm based on the Arnoldi iteration ispresented. This algorithm is as computationallyefficient asthe one used to generate guaranteed-stable reduced-ordermodels [Coordinate-transformed Arnoldi for generating guranteed stable reduced-order models for RLC circuits].

Resource control for large-scale distributed simulation system over loosely coupled domains