33219357
Fault-tolerant broadcasting in wormhole-routed torus networks
This paper describes a fault-tolerant broadcast algorithm for wormhole-routed torus networks for which there is only local knowledge of faulty components. This algorithm tolerates tip to k-1 faulty nodes in a k-ary n-cube provided the faults do not cause the network to be disconnected. Based on the fault-tolerant dimension-order unicast communication, this algorithm is deadlock-free and no additional virtual channels are needed. The first stage of this algorithm is itself an optimal broadcast algorithm for a torus if no faults are present. The second stage overcomes the presence of up to k-1 faults with a fixed number of additional message transmissions. Thus, the cost of this algorithm is within a constant factor of the cost of optimal non-fault-tolerant broadcast algorithms.
29785948
Fast Replacement Route Discovery in Location-Aided Mobile Ad hoc Networks
35581387
Cluster-based Location Discovery in Ad Hoc Sensor Networks
34087964
Wormhole Routing in Faulty Mesh Networks
42767167
Location Discovery in Ad Hoc Sensor Networks
46184949
Adaptive Deadlock-Free Wormhole Routing in Faulty Hypercubes
6873960
A scalable approach for reliable downstream data delivery in wireless sensor networks
There exist several applications of sensor networks wherere liability of data delivery can be critical. While the redundancy inherent in a sensor network might increase the degree of reliability, it by no means can provide any guaranteed reliability semantics. In this paper, we consider the problem of reliable sink-to-sensors data delivery. We first identify several fundamental challenges that need to be addressed, and are unique to a wireless sensor network environment. We then propose a scalable framework for reliable downstream data delivery that is specifically designed to both address and leverage the characteristics of a wireless sensor network, while achieving the reliability in an efficient manner. Through ns2 based simulations, we evaluate the proposed framework.
9375021
Dynamic Data Grid Replication Strategy Based on Internet Hierarchy
In data grid, large quantity of data files is produced and data replication is applied to reduce data access time. Efficiently utilizing grid resources becomes important research issue since available resources in grid are limited while large number of workloads and large size of data files are produced. Dynamic replication in data grid aims to reduce data access time and to utilize network and storage resources efficiently. This paper proposes a novel dynamic replication strategy, called BHR, which reduces data access time by avoiding network congestions in a data grid network. With BHR strategy, we can take benefits from ‘network-level locality’ which represents that required file is located in the site which has broad bandwidth to the site of job execution. We evaluate BHR strategy by implementing it in an OptorSim, a data grid simulator initially developed by European Data Grid Projects. The simulation results show that BHR strategy can outperform other optimization techniques in terms of data access time when hierarchy of bandwidth appears in Internet. BHR extends current site-level replica optimization study to the network-level.
37317818
Practice and Experience of an Embedded Processor Core Modeling
This paper presents our experience in developing an embedded processor core model for an SOC design. We developed an ARM1136 processor simulation environment based on the ARM's MaxCore tool and the SimpleScaclar simulator. A MaxCore ARM1136 instruction accurate (IA) model is developed to support application programmers for the writing application programs from the early design stage. The MaxCore ARM1136 processor model supports all ARMv4, ARMv5TE and ARM v6 instruction sets with 418 LISA instructions. This MaxCore IA Model can be integrated with the ARM's MaxSim system level design environment to develop application softwares and perform architecture explorations. A SimpleScalar ARM1136 cycle accurate (CA) model is also developed by enhancing the existing SimpleScalar-ARM version in the SimpleScalar 3.0. Most important micro-architectural features of ARM1136 processor are implemented in the enhanced SimpleScalar simulator. The accuracy of the developed SimpleScalar-ARM 1136 simulator is about 97% compared to ARM 1136 RTL simulation with the Dhrystone benchmark (100 iterations).
9401551
Sink-to-sensors reliability in sensor networks
The issue of relability, thus far, has not been addressed throughly to any extent in sensor networking research. To the best of our knowledge the first such work that focused on some aspect of reliable communication in sensor networks appeared only in [1]. In this paper, we focus on the problem of communication reliability from the sink to the sensors in a static network.
15182689
Chameleon: a resource scheduler in a data grid environment
Grid computing is moving into two ways. The Computational Grid focuses on reducing execution time of applications that require a great number of computer processing cycles. The Data Grid provides the way to solve large scale data management problems. Data intensive applications such as High Energy Physics and Bioinformatics require both Computational and Data Grid features. Job scheduling in Grid has been mostly discussed from the perspective of computational Grid. However, scheduling on Data Grid is just a recent focus of Grid computing activities. In Data Grid environment, effective scheduling mechanism considering both computational and data storage resources must be provided for large scale data intensive applications. In this paper, we describe new scheduling model that considers both amount of computational resources and data availability in Data Grid environment. We implemented a scheduler, called Chameleon, based on the proposed application scheduling model. Chameleon shows performance improvements in data intensive applications that require both large number of processors and data replication mechanisms. The results achieved from Chameleon are presented.