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First Field Trial of Optical Label-Based Switching and Packet Drop on a 477km NTON/Sprint Link

Description: We demonstrate the first field trial of optical label-based wavelength switching and packet drop on 476.8km of the National Transparent Optical Network. Subcarrier multiplexed labels control a switch fabric that includes a tunable wavelength converter and arrayed waveguide grating router.
Date: December 10, 2001
Creator: Hernandez, V. J.; Pan, Z.; Cao, J.; Tsui, V. K.; Bansal, Y.; Fong, S. K. H. et al.
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Partner: UNT Libraries Government Documents Department
open access

PADRE: a parallel asynchronous data routing environment

Description: Increasingly in industry, software design and implementation is object-oriented, developed in C++ or Java, and relies heavily on pre-existing software libraries (e.g. the Microsoft Foundation Classes for C++, the Java API for Java). A similar but more tentative trend is developing in high-performance parallel scientific computing. The transition from serial to parallel application development considerably increases the need for library support: task creation and management, data distribution an… more
Date: January 8, 2001
Creator: Gunney, B & Quinlan, D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Data Transport in a Novel Wireless Sensor Network

Description: The deployment and operation of large wireless sensor networks can pose difficult problems, particularly in time critical situations, over large geographic areas, or in rugged terrain. An approach to this problem is to use unmanned air vehicles to first deploy the sensors, and then provide communication services to the sensors. This paper presents a network model that describes the flow of data through such a sensor network. Simulation results are presented that illustrate the behavior of the d… more
Date: June 1, 2001
Creator: Roberts, R S
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Partner: UNT Libraries Government Documents Department
open access

Effective Communication and File-I/O Bandwidth Benchmarks

Description: We describe the design and MPI implementation of two benchmarks created to characterize the balanced system performance of high-performance clusters and supercomputers: b{_}eff, the communication-specific benchmark examines the parallel message passing performance of a system, and b{_}eff{_}io, which characterizes the effective 1/0 bandwidth. Both benchmarks have two goals: (a) to get a detailed insight into the Performance strengths and weaknesses of different parallel communication and I/O pa… more
Date: May 2, 2001
Creator: Koniges, A E & Rabenseifner, R
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Partner: UNT Libraries Government Documents Department
open access

Bayesian Spectroscopy and Target Tracking

Description: Statistical analysis gives a paradigm for detection and tracking of weak-signature sources that are moving among a network of detectors. The detector platforms compute and exchange information with near-neighbors in the form of Bayesian probabilities for possible sources. This can shown to be an optimal scheme for the use of detector information and communication resources. Here, we apply that paradigm to the detection and discrimination of radiation sources using multi-channel gamma-ray spectr… more
Date: May 1, 2001
Creator: Cunningham, C
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

D0 Silicon Strip Detector Upgrade Project SVX Sequencer Controller Board

Description: The Sequencer Controller boards are 9U by 340mm circuit boards that will reside in slot 1 of each of eight Sequencer crates in the D0 detector platform. The primary purpose is to control the Sequencers during data acquisition based on trigger information from the D0 Trigger Framework. Functions and features are as follows: (1) Receives the Serial Command Link (SCL) from the D0 Trigger System and controls the operation of the Sequencers by forming a custom serial control link (NRZ/Clock) which i… more
Date: May 29, 2001
Creator: Utes, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

An inter-realm, cyber-security infrastructure for virtual supercomputing

Description: Virtual supercomputing, (ise ., high-performance grid computing), is poised to revolutionize the way we think about and use computing. However, the security of the links interconnecting the nodes within such an environment will be its Achilles heel, particularly when secure communication is required to tunnel through heterogeneous domains. In this paper we examine existing security mechanisms, show their inadequacy, and design a comprehensive cybersecurity infrastructure that meets the security… more
Date: January 1, 2001
Creator: Al-Muhtadi, J. (Jalal); Feng, W. C. (Wu-Chun) & Fisk, M. E. (Mike E. )
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Dynamic right-sizing in TCP : a simulation study /

Description: Virtually all network applications requiring reliable end-to-end communication depend on TCP. Unfortunately, the performance of any stock TCP is abysmal over wide-area networks (WANs) and even over local area networks (LANs) with wry high-bandwidth links. Currently, network researchers manually optimize TCP buffer sizes to achieve acceptable performance over a given connection. Unfortunately, this manual optimhtlon requires changes to the kernel on both end hosts involved in the network connect… more
Date: January 1, 2001
Creator: Weigle, E. H. (Eric H.) & Feng, W. C. (Wu-Chun)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Hardware-and-software-based collective communication on the Quadrics network.

Description: The efficient implementation of collective communication patterns in a parallel machine is a challenging design effort, that requires the solution of many problems. In this paper we present an in-depth description of how the Quadrics network supports both hardware- and software-based collectives. We describe the main features of the two building blocks of this network, a network interface that can perform zero-copy user-level communication and a wormhole switch. We also focus our attention on t… more
Date: January 1, 2001
Creator: Petrini, F. (Fabrizio); Coll, S. (Salvador); Frachtemberg, E. (Eitan) & Hoisie, A. (Adolfy)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

MAGNeT : Monitor for Application-Generated Network Traffic /

Description: Over the laqt decade, network practitioners have focused on monitoring, measuring, and characterizing traffic in the network to gain insight into building critical network components (from the protocol stack to routers and switches to network interface cards). Recent research shows that additional insight can be obtained by monitoring traffic at the application level (Le,, before application-sent traffic is modulated by the protocol stack) rather than in the network (i-e., after it is modulated… more
Date: January 1, 2001
Creator: Feng, W. C. (Wu-Chun); Hay, J. R. (Jeffrey R.) & Gardner, M. K. (Mark K.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Authentication of quantum messages.

Description: Authentication is a well-studied area of classical cryptography: a sender A and a receiver B sharing a classical private key want to exchange a classical message with the guarantee that the message has not been modified or replaced by a dishonest party with control of the communication line. In this paper we study the authentication of messages composed of quantum states. We give a formal definition of authentication in the quantum setting. Assuming A and B have access to an insecure quantum ch… more
Date: January 1, 2001
Creator: Barnum, Howard; Crépeau, Jean-Claude; Gottesman, D. (Daniel); Smith, A. (Adam) & Tapp, Alan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Next generation epics interface to abstract data.

Description: The set of externally visible properties associated with process variables in the Experimental Physics and Industrial Control System (EPICS) is predefined in the EPICS base distribution and is therefore not extensible by plug-compatible applications. We believe that this approach, while practical for early versions of the system with a smaller user base, is now severely limiting expansion of the high-level application tool set for EPICS. To eliminate existing barriers, we propose a new C++ base… more
Date: January 1, 2001
Creator: Hill, J. O. (Jeffrey O.) & Lange, R. (Ralph)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Case for TCP Vegas in High-Performance Computational Grids

Description: Computational grids such as the Information Power Grid, Particle Physics Data Grid, and Earth System Grid depend on TCP to provide reliable communication between nodes across a wide-area network (WAN). Of the available TCP implementations, TCP Reno and its variants are the most widely deployed; however, Reno's performance in computational grids is mediocre at best. Due to conflicting results in the evaluation of TCP implementations we present a detailed simulation study that unifies the conflic… more
Date: January 1, 2001
Creator: Weigle, E. H. (Eric H.) & Feng, W. C. (Wu-Chun)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A Comparative experimental study of media access protocols for wireless radio networks

Description: We conduct a comparative experimental analysis of three well known media access protocols: 802.11, CSMA, and MACA for wireless radio networks. Both fixed and ad-hoc networks are considered. The experimental analysis was carried out using GloMoSim: a tool for simulating wireless networks. The main focus of experiments was to study how (i) the size of the network, (ii) number of open connections, (iii) the spatial location of individual connections, (iv) speed with which individual nodes move and… more
Date: May 24, 2001
Creator: Barrett, C. L. (Christopher L.); Drozda, M. (Martin) & Marathe, M. V. (Madhav V.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

High-performance networking.

Description: Our research in high-performance networking addresses the communication needs of Grand Challenge applications over a wide range of environments - wide-area network (WAN) in support of grids and local-area network (LAN) and system-area network (SAN) in support of network of workstations and clusters. While the high-performance computing (HPC) community generally groups clusters and grids together as commodity supercomputing infrastructures, the networking aspects of clusters and grids are fundam… more
Date: January 1, 2001
Creator: Feng, W. C. (Wu-Chun)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

EFFECT OF MOBILITY ON PERFORMANCE OF WIRELESS AD-HOC NETWORK PROTOCOLS.

Description: We empirically study the effect of mobility on the performance of protocols designed for wireless adhoc networks. An important ohjective is to study the interaction of the Routing and MAC layer protocols under different mobility parameters. We use three basic mobility models: grid mobility model, random waypoint model, and exponential correlated random model. The performance of protocols was measured in terms of (i) latency, (ii) throughput, (iii) number of packels received, (iv) long term fair… more
Date: January 1, 2001
Creator: Barrett, C. L. (Christopher L.); Drozda, M. (Martin); Marathe, M. V. (Madhav V.) & Marathe, A. (Achla)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

MAGNET TOOLKIT: DESIGN, IMPLEMENTATION, AND EVALUATION.

Description: The current trend in constructing high-performance computing systems is to connect a large number of machines via a fast interconnect or a large-scale network such as the Internet, This approach relies on the performance of the interconnect (or Internet) to enable Past, large-scale distributed computing. A detailed understanding of the communication traffic is required in order to optimize the operation of entire system. Network researchers traditionally monitor traffic in the network to gain t… more
Date: January 1, 2001
Creator: Hay, J. R. (Jeffrey R.); Feng, W. C. (Wu-Chun) & Gardner, M. K. (Mark K.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Avian Collisions with Wind Turbines: A Summary of Existing Studies and Comparisons to Other Sources of Avian Collision Mortality in the United States

Description: It has been estimated that from 100 million to well over 1 billion birds are killed annually in the United States due to collisions with human-made structures, including vehicles, buildings and windows, powerlines, communication towers, and wind turbines. Although wind energy is generally considered environmentally friendly (because it generates electricity without emitting air pollutants or greenhouse gases), the potential for avian fatalities has delayed and even significantly contributed to … more
Date: August 1, 2001
Creator: Wallace P. Erickson, Gregory D. Johnson, M. Dale Strickland, David P. Young, Jr., Karyn J. Sernka, Rhett E. Good
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

SUBSURFACE VISUAL ALARM SYSTEM ANALYSIS

Description: The ''Subsurface Fire Hazard Analysis'' (CRWMS M&O 1998, page 61), and the document, ''Title III Evaluation Report for the Surface and Subsurface Communication System'', (CRWMS M&O 1999a, pages 21 and 23), both indicate the installed communication system is adequate to support Exploratory Studies Facility (ESF) activities with the exception of the mine phone system for emergency notification purposes. They recommend the installation of a visual alarm system to supplement the page/party … more
Date: August 6, 2001
Creator: Markman, D.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A comparison of three programming models for adaptive applications on the Origin2000

Description: Adaptive applications have computational workloads and communication patterns which change unpredictably at runtime, requiring dynamic load balancing to achieve scalable performance on parallel machines. Efficient parallel implementations of such adaptive applications is therefore a challenging task. In this paper, we compare the performance of and the programming effort required for two major classes of adaptive applications under three leading parallel programming models on an SGI Origin2000 … more
Date: May 30, 2001
Creator: Shan, Hongzhang; Singh, Jaswinder Pal; Oliker, Leonid & Biswas, Rupak
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A practical approach to the interGroup protocols

Description: Existing reliable ordered group communication protocols have been developed for local-area networks and do not, in general, scale well to large numbers of nodes and wide-area networks. The InterGroup suite of protocols is a scalable group communication system that introduces an unusual approach to handling group membership, and supports a receiver-oriented selection of service. The protocols are intended for a wide-area network, with a large number of nodes, that has highly variable delays and … more
Date: November 12, 2001
Creator: Berket, Karlo; Agarwal, Deborah A. & Chevassut, Olivier
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development of a Comprehensive Wireless Communications System for the Underground Mining Industry

Description: Progress continued along both subsystems towards an integrated comprehensive wireless communications system for the underground mining industry. Designing an automated continuous self-tuning mechanism that optimizes signal transmission intensity for a given power input enhanced through-the-earth communications. In-mine communications was enhanced through the design of a circuit that eliminates multi-antenna interference, cleaning-up the received signal.
Date: April 2001
Creator: Meiksin, Zvi H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Low-Dose Risk, Decisions, and Risk Communication

Description: To conduct basic research on how people receive, evaluate, and form positions on scientific information and its relationship to low-dose radiation exposure. There are three major areas of study in our research program. First is the development of theories, frameworks and concepts essential to guiding data collection and analysis. The second area is a program of experimental studies on risk perception, evaluation of science information, and the structure of individual positions regarding low dos… more
Date: June 1, 2001
Creator: Flynn, James & Slovic, Paul
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Final Report on Internet Addressable Lightswitch

Description: This report describes the work performed to develop and test a new switching system and communications network that is useful for economically switching lighting circuits in existing commercial buildings. The first section of the report provides the general background of the IBECS (Integrated Building Environmental Communications System) research and development work as well as the context for the development of the new switching system. The research and development effort that went into produc… more
Date: August 27, 2001
Creator: Rubinstein, Francis & Pettler, Peter
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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