Glossary

ACTS

Advanced Communications Technology Satellite, a NASA-sponsored program. A joint NASA/ARPA collaboration will demonstrate high speed ATM/SONET transmission over the ACTS satellite, and will provide interface and operations experience in mating high speed terrestrial communications systems with high speed satellite communications systems.

AERONet

Aeronautics Network in NASA

AFS

Andrew File System

AHCPR

Agency for Health Care Policy and Research, part of the Public Health Service of the HHS

AIMS

Automated Instrumentation and Monitoring System

Algorithm

A procedure designed to solve a problem. Scientific computing programs contain algorithms.

ARPA

Advanced Research Projects Agency, part of DOD

ARPANet

Advanced Research Projects Agency Network

ASTA

Advanced Software Technology and Algorithms, a component of the HPCC Program

ATDNet

Advanced Technology Demonstration Network

ATM

Asynchronous Transfer Mode, a telecommunications technology, also known as cell switching, which is based on 53-byte cells

Backbone Network

A high capacity electronic trunk connecting lower capacity networks, for example the NSFNET backbone

Bandwidth

A measure of the capacity of a communications channel to transmit information; for example, million of bits per second or Mb/s

Benchmark

A point of reference (artifact) to compare an aspect of systems performance (for example, a well-known set of programs); also, to conduct and assess the computation (or transmission) capabilities of a system using a well-known artifact

Bit

Acronym for binary digit

Bps, or B/s

An acronym for bytes per second

bps, or b/s

An acronym for bits per second

BRHR

Basic Research and Human Resources, a component of the HPCC Program

Browser

A system that provides access to and rendering of distributed information objects located at network-based repositories; that is, services allowing a user to locate, access, and display information composed of text and still images; to animate moving images; and to play associated sound tracks. Mosaic is an example of a public- domain browser.

Byte

A group of adjacent binary digits operated upon as a unit (usually connotes a group of eight bits)

C

C programming language

C++

C++ programming language, an object-oriented descendant of the C language

CAD

Computer Aided Design

CERT

Computer Emergency Response Team

CIAC

Computer Incident Advisory Center

CIC

Committee on Information and Communications of the NSTC

Computational Science and Engineering

The systematic application of computing systems and computational solution techniques to mathematical models formulated to describe and simulate phenomena of scientific and engineering interest

Computer Engineering

The creative application of engineering principles and methods to the design and development of hardware and software systems

Computer Science

The systematic study of computing systems and computation. The body of knowledge resulting from this discipline contains theories for understanding computing systems and methods; design methodology, algorithms, and tools; methods for the testing of concepts; methods of analysis and verification; and knowledge representation and implementation.

CRPC

Center for Research in Parallel Computation

CTC

Cornell Theory Center

Database

A collection of information

Database server

A system that provides database access services to users via client software systems

DCE

Distributed Computing Environment

DCRT

Division of Computer Research and Technology, part of NIH

DFS

Distributed File System

DII

Defense Information Infrastructure

DOC

Department of Commerce

DOD

Department of Defense

DOE

Department of Energy

ED

Department of Education

e-mail

electronic mail

Encryption

A reversible transformation of the encoding of information into a form that is unintelligible to unauthorized recipients in order to ensure the privacy of the information being communicated Ð an algorithm, the encoded information, and a key are used to encrypt (transform) and decrypt (reverse-transform) information.

EPA

Environmental Protection Agency

ESnet

Energy Sciences Network

ESS

Earth and Space Sciences

Exa-

A prefix denoting 1018, or a million trillions of ... (for example, exabytes)

FDDI

Fiber Distributed Data Interface

Flops

Acronym for floating point operations per second. The term "floating point" refers to that format of numbers that is most commonly used for scientific calculation. Flops is used as a measure of a computing system's speed of performing basic arithmetic operations such as adding, subtracting, multiplying, or dividing two numbers.

FNC

Federal Networking Council

ftp

file transfer protocol

G, or Giga-

A prefix denoting 109, or billions of ... (for example, Gflops or gigaflops; gigabytes, gigabits)

GAO

Government Accounting Office

Gateway

A system that interconnects networks (or applications) that communicate using different protocols, and bridges their differences by transforming one protocol (message) into another

GB

An acronym for Gigabyte

Gb

An acronym for Gigabit

Gb/s

Gigabits per second

GFDL

Geophysical Fluid Dynamics Laboratory

Gflops

Gigaflops, billions of floating point operations per second

GII

Global Information Infrastructure

Grand Challenge

A fundamental problem in science and engineering, with broad economic and scientific impact, whose solution can be advanced by applying high performance computing techniques and resources

GSII

Government Services Information Infrastructure

Heterogeneous system

A distributed system that contains more than one kind of computer

HHS

Department of Health and Human Services

High performance computing

Covers the full range of advanced computing systems including workstations, networks of workstations with servers, scalable parallel systems, vector parallel systems, and more specialized systems. Scalable input/output interfaces, mass storage systems, and archival storage are components of these systems. Included also are system software and software development environments that enable users to view their workstations and the rest of their computing environments as a unified system.

HiPPI

High Performance Parallel Interface, 800 Mb/s

HPCC

High Performance Computing and Communications

HPCCI

High Performance Computing and Communications Initiative

HPCCIT

High Performance Computing, Communications, and Information Technology Subcommittee, part of the CIC

HPCS

High Performance Computing Systems, a component of the HPCC Program

HPF

High Performance Fortran

HPSS

High Performance Storage System

html

Hypertext markup language, a text composition language that allows an author to compose the contents of a document (file) that may contain text, still and moving images, and audio (multimedia objects) and have embedded links to files (multimedia objects) located on other computing systems via uniform resource locators (URLs). The ability to embed links (URLs) to multimedia objects located at distributed servers on the Internet and the ability of browsers to link to and render multimedia objects is what realizes hypertext.

http

Hypertext transport protocol, the communications protocol used by WWW servers and client systems to identify sources of information and transfer the files containing html-based multimedia objects

I/O

Acronym for Input/Output

IETF

Internet Engineering Task Force

IITA

Information Infrastructure Technology and Applications, a component of the HPCC Program

Interconnectivity

The ability of two or more computers to easily locate and communicate with each other over an infrastructure that provides the speed and clarity to accomplish a proposed task

Internet

The global collection of interconnected, multiprotocol computer networks including Federal, mid-level, private, and international networks.

Interoperability

The ability of any two computers that are interconnected to understand each other and perform mutually supportive tasks such as client/server computing

IP

Internet Protocol

ISS

Image Server Systems

JNNIE

Joint NSF-NASA Initiative on Evaluation

JPL

Jet Propulsion Laboratory

K, or Kilo-

A prefix denoting 103, or thousands of ... (for example, kilobits/second)

Kb/s

Kilobits per second or thousands of bits per second

Kerberos

A cryptographic-based network system that provides a mechanism for client/server computing authentication

LANL

Los Alamos National Laboratory

LLNL

Lawrence Livermore National Laboratory

M, or Mega-

A prefix denoting 106, or millions of ... (for example, Mbps, or megabits per second; Mflops)

MB

Megabyte

Mb

Megabit

Mb/s

Megabits per second or millions of bits per second

MBONE

Multicast backbone

Metacenter

A virtual supercomputing center composed of the networked high performance computing resources at several supercomputing centers

Mflops

Megaflops, millions of floating point operations per second.

MILNET

Military Network

MIMD

Multiple Instruction Multiple Data

MOSIS

Metal Oxide Semiconductor Implementation Service

MP

Massively Parallel

MPI

Message passing Interface

MPP

Massively parallel processor

MRAs

Metacenter Regional Alliance

Multicast

A mode of communications that allows for simultaneous distribution of information to multiple designated recipients in a single transmission

NAPs

Network Access Points, networks or switches where multiple networks interconnect to exchange traffic

NASA

National Aeronautics and Space Administration

National Challenge

A fundamental application that has broad and direct impact on the Nation's competitiveness and the well-being of its citizens, and that can benefit from the application of HPCC technology and resources

National Information Infrastructure (NII)

The integration of hardware, software, and skills that will make it easy and affordable to connect people with each other, with computers, and with a vast array of services and information resources

NCAR

National Center for Atmospheric Research

NCBI

National Center for Biotechnology Information

NCI

National Cancer Institute, part of NIH

NCO

National Coordination Office for High Performance Computing and Communications

NCRR

National Center for Research Resources, part of NIH

NCSA

National Center for Supercomputing Applications

NERSC

National Energy Research Supercomputer Center

Network

Computer communications technologies that link multiple computers to share information and resources across geographically dispersed locations

NIH

National Institutes of Health, part of HHS

NIST

National Institute of Standards and Technology, part of DOC

NLM

National Library of Medicine, part of NIH

NOAA

National Oceanic and Atmospheric Administration, part of DOC

NREN

National Research and Education Network, a component of the HPCC Program

NSA

National Security Agency, part of DOD

NSF

National Science Foundation

NSFNET

NSF computer network program

NSI

NASA Science Internet

NSL

National Storage Laboratory

NSTC

National Science and Technology Council

OMB

Office of Management and Budget

Ops

Acronym for operations per second. Ops is used as a rating of the speed of computer systems and components. In this report ops is generally taken to mean the usual integer or floating point operations depending on what functional units are included in a particular system configuration.

Optoelectronic

A descriptor of technology which combines optical and electronic components

ORNL

Oak Ridge National Laboratory

OS

Operating system

OSTP

White House Office of Science and Technology Policy

Parallel processing

Simultaneous processing by more than one processing unit on a single application

PC

Personal computer

Peta-

A prefix denoting 1015, or a thousand trillion of ... (for example, petabits)

PICS

Partnership in Computational Sciences

PMEL

Pacific Marine Environmental Laboratory

Port

Transport a computer program from one computer system to another

Portable

Property of some computing software that allows the software to be run with little or no change on many kinds of computing systems

Prototype

The original demonstration model of what is expected to be a series of systems. Prototypes are used to prove feasibility, but often are not as efficient or well-designed as later production models.

PSC

Pittsburgh Supercomputer Center

PVM

Parallel Virtual Machine

RAID

Redundant Arrays of Inexpensive Disks

R&D

Research and development

Scalable

A system is scalable if it can be made to have more (or less) computational power by configuring it with a larger (or smaller) number of processors, amount of memory, interconnection bandwidth, input/output bandwidth, and amount of mass storage.

SDSC

San Diego Supercomputer Center

SIMD

Single Instruction Multiple Data

SONET

Synchronous Optical Network

STEP

Standard for the Exchange of Product Model Data

Superlinear

A relationship that is greater than a simple linear relationship (for example, multiple or fraction), but one that is not an exponential or geometric relationship

T, or Tera-

A prefix denoting 1012 or trillions of ... (for example, terabits, teraflops)

T1

Network transmission of a digital signal at 1.5 Mb/s (DS-1)

T3

Network transmission of a digital signal at 45 Mb/s (DS-3)

TCP/IP

Transmission Control Protocol/Internet Protocol

TRP

Technology Reinvestment Program

URL

Uniform Resource Locator

VA

Department of Veterans Affairs

vBNS

Very high speed Backbone Network Services

VLSI

Very large scale integration

VR

Virtual reality

WAIS

Wide Area Information Service

Web

A reference to the World Wide Web; a subset of the Internet supported by a related set of protocols, services, and software tools including browsers.

Wireless technologies

Communications technologies that utilize radio, microwave, or satellite communications channels versus wire, coaxial or optical fiber

WWW

World Wide Web