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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 � 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