Glossary of Internet Terms

ACM

Association for Computer Machinery: a group established in 1947 to promote professional development and research on computers.

address

There are two separate uses of this term in Internet networking: "electronic mail address" and "Internet address." An electronic mail address is the string of characters that you must give an electronic mail program to direct a message to a particular person. See "Internet address" for its definition.

AI

Artificial Intelligence: the branch of computer science which deals with the simulation of human intelligence by computer systems.

AIX

Advanced Interactive Executive: IBM's version of Unix.

ANSI

American National Standards Institute: a group that defines U.S. standards for the information processing industry. ANSI participates in defining network protocol standards.

ARCHIE

A system for locating files that are publicly available by anonymous FTP. And yes, it was named after the old cartoon character.

ARPA

Advanced Research Projects Agency: the former name of what is now called DARPA.

ARPANET

Advanced Research Projects Agency Network: a pioneering long haul network funded by ARPA. It served as the basis for early networking research as well as a central backbone during the development of the Internet. The ARPANET consisted of individual packet switching computers interconnected by leased lines.

ASCII

American Standard Code for Information Interchange. A standard method of encoding characters as numbers for transmission and storage by computers. A space is 32, an exclamation point is 33, an upper case "A" is 65, a lower case "a" is 97, etc. Often mispronounced as "ah-ski two" instead of the proper "ah-ski."

B

Byte: one character of information, usually eight bits wide.

b

bit - binary digit: the smallest amount of information which may be stored in a computer.

baud

When transmitting data, the number of times the medium's "state" changes per second. Not a valid indication of speed except for very slow connections.

BBN

Bolt, Beranek, and Newman, Inc.: the Cambridge, MA, company responsible for development, operation and monitoring of the ARPANET, and later, the Internet core gateway system, the CSNET Coordination and Information Center (CIC), and NSFnet Network Service Center (NNSC).

BITNET

Because It's Time Network: BITNET has several thousand host computers, primarily at universities and in many countries. It is managed by EDUCOM, which provides administrative support and information services. There are three main constituents of the network: BITNET in the United States and Mexico, NETNORTH in Canada, and EARN in Europe. There are also AsiaNet in Japan and connections in South America. See CREN.

bps

bits per second: a measure of data transmission speed. When people talk about the "baud rate" of a connection, they probably mean "bits per second" but don't know the difference.

BSD

Berkeley Software Distribution: term used when describing different versions of the Berkeley UNIX software, as in "4.3BSD UNIX."

CCITT

International Consultative Committee for Telegraphy and Telephony, an international standards board.

CISC

Complex Instruction Set Computing. All Apple computers prior to the introduction of the Power Macs and Newtons were based on CISC processors. All MS-DOS, Windows 3.1 and Windows 95 computers use CISC processors. See RISC.

CNRI

Corporation for National Research Initiatives.

COSINE

Cooperation for Open Systems Interconnection Networking in Europe

CREN

The Corporation for Research and Educational Networking: COREN, BITNET and CSNET have recently merged to form CREN.

CSNET

Computer + Science Network: a large data communications network for institutions doing research in computer science. It uses several different protocols including some of its own. CSNET sites include universities, research laboratories, and commercial companies. See CREN.

DARPA

U.S. Department of Defense Advanced Research Projects Agency: the government agency that funded the ARPANET and later started the Internet.

datagram

The unit transmitted between a pair of Internet modules. The Internet Protocol provides for transmitting blocks of data, called datagrams, from sources to destinations.

DCA

Defense Communications Agency: the government agency responsible for installation of the Defense Data Network (DDN), including the ARPANET and MILNET lines and PSNs. Currently, DCA administers the DDN, and supports the user assistance and network registration services of the DDN NIC.

DDN

Defense Data Network: comprises the MILNET and several other Department of Defense networks.

DDN NIC

The network information center at SRI International. It is the primary repository for Request for Comments (RFC) and Internet drafts, as well as providing other services.

dedicated line

A permanently connected private telephone line between two locations.

DOD

U.S. Department of Defense.

DOE

U.S. Department of Energy.

download

To transfer files from one computer to another.

DNS

Domain Name System: a mechanism used in the Internet for translating names of host computers into addresses. The DNS also allows host computers not directly on the Internet to have registered names in the same style.

EARN

European Academic Research Network: one of three main constituents of BITNET.

EBCDIC

Extended Binary-Coded Decimal Interchange Code. Used by some older IBM mainframes, EBCDIC was a failed attempt to come up with a better coding scheme than ASCII.

email

The vernacular abbreviation for electronic mail.

Ethernet

A network standard for the hardware and data link levels. There are two types of Ethernet: Digital/Intel/Xerox (DIX) and IEEE 802.3.

FAQ

Frequently Asked Questions: a list with their answers. Most mailing lists and all network newsgroups provide FAQ postings on a regular basis.

FDDI

Fiber Distributed Data Interface: FDDI is a high-speed (100 Mb) token ring LAN.

FIPS

Federal Information Processing Standard.

FTP

File Transfer Protocol: the Internet standard high-level protocol for transferring files from one computer to another.

gateway

A special-purpose dedicated computer that attaches to two or more networks and routes packets from one network to the other. In particular, an Internet gateway routes IP datagrams among the networks it connects. Gateways route packets to other gateways until they can be delivered to the final destination directly across one physical network. See router.

GB

Gigabyte: a unit of data storage size which represents one billion characters of information.

Gb

Gigabit: One billion bits of information (usually used to express a data transfer rate; as in, 1 gigabit/second = 1Gbps).

GNU

Gnu's Not UNIX: A UNIX-compatible operating system developed by the Free Software Foundation.

Gopher

A menu-based system for exploring Internet resources developed by the University of Minnesota. Well suited for text-only connections, it is being rapidly overshadowed by the sexier graphical interface of the World Wide Web. The name honors the University of Minnesota Golden Gophers.

header

The portion of a packet, preceding the actual data, containing source and destination addresses and error-checking fields.

host number

The part of an Internet address that designates which node on the (sub)network is being addressed.

I/O

Input/Output.

IEEE

Institute for Electrical and Electronics Engineers.

internetwork

Any connection of two or more local or wide-area networks.

Internet

The global collection of interconnected regional and wide-area networks which use IP as the network layer protocol.

Internet address

An assigned number which identifies a host in an internet. It has two or three parts: network number, optional subnet number, and host number.

IP

Internet Protocol: The network layer protocol for the Internet. It is the datagram protocol defined by RFC 791.

ISDN

Integrated Services Digital Network, essentially an expensive, high-capacity telephone line.

ISO

International Standards Organization.

KB

Kilobyte: A unit of data storage size which represents 1,024 characters of information.

Kb

Kilobit: 1,024 bits of information (usually used to express a data transfer rate; as in, 1 kilobit/second = 1Kbps).

Knowbot

An experimental information-retrieval tool; a "knowledge robot" or "robot librarian."

LAN

Local Area Network: a network that takes advantage of the proximity of computers to offer relatively efficient, higher speed communications than long-haul or wide-area networks.

MAC

Medium Access Control: for broadcast networks, it is the method which devices use to determine which device has line access at any given time.

Macintosh

Macintosh is Apple Computer Corporation's name for their series of MacOS-based computers. These have become the personal computer of choice for exploring the Internet.

MacOS

MacOS is the non-manufacturer-specific name given to the Macintosh operating system, used on computers manufactured by Apple, Power Computing, DayStar Digital, Radius and others.

MAN

Metropolitan Area Network.

MB

Megabyte: a unit of data storage size which represents one million characters of information.

Mb

Megabit: one million bits of information (usually used to express a data transfer rate; as in, 1 megabit/second = 1Mbps).

MILNET

Military Network: a network used for unclassified military production applications. It is part of the Internet.

MTTF

Mean Time to Failure: the average time between hardware breakdown or loss of service. This may be an empirical measurement or a calculation based on the MTTF of component parts.

MTTR

Mean Time to Recovery: the average time it takes to restore service after a breakdown or loss. This is usually an empirical measurement.

MVS

Multiple Virtual Storage: an IBM operating system based on OS/1.

modem

A piece of equipment that connects a computer to a data transmission line (typically a telephone line).

NASA

U.S. National Aeronautics and Space Administration.

NBS

U.S. National Bureau of Standards: now called NIST.

network number

The part of an internet address which designates the network to which the addressed node belongs.

NFS

Network File System: a network service that lets a program running on one computer to use data stored on a different computer on the same internet as if it were on its own disk.

NIC

Network Information Center: an organization which provides network users with information about services provided by the network.

NII

National Information Infrastructure.

NIST

U.S. National Institute of Standards and Technology: Formerly NBS.

NOAA

U.S. National Oceanic and Atmospheric Administration.

NOC

Network Operations Center: an organization which is responsible for maintaining a network.

NREN

National Research and Education Network.

NSF

National Science Foundation.

NSFNET

National Science Foundation Network: a high-speed internet that spans the country, and is intended for research applications. It is made up of the NSFnet Backbone and the NSFnet regional networks. It is part of the Internet.

NSFNET Backbone

A network connecting 21 sites across the continental United States. It is the central component of NSFnet.

OSI

Open Systems Interconnection: a set of protocols designed to be an international standard method for connecting unlike computers and networks. Europe has done most of the work developing OSI and will probably use it as soon as possible.

packet

The unit of data sent across a packet switching network. The term is used loosely. While some Internet literature uses it to refer specifically to data sent across a physical network, other literature views the Internet as a packet switching network and describes IP datagrams as packets.

PCNFS

Personal Computer Network File System.

POP

Post Office Protocol: a type of mail protocol designed for easier administration of SMTP mail services.

POSIX

Portable Operating System Interface: operating system based on UNIX.

PPP

Point-to-Point Protocol: provides a method for transmitting datagrams over serial point-to-point links.

protocol

A formal description of message formats and the rules two computers must follow to exchange those messages. Protocols can describe low-level details of machine-to-machine interfaces (e.g., the order in which bits and bytes are sent across a wire) or high-level exchanges between allocation programs (e.g., the way in which two programs transfer a file across the Internet).

RFC

The Internet's Request for Comments documents series: the RFCs are working notes of the Internet research and development community. A document in this series may be on essentially any topic related to computer communication, and may be anything from a meeting report to the specification of a standard.

RISC

Reduced Instruction Set Computing. The Power Macintosh computers are the only RISC-based personal computers (the Newton uses a RISC processor, too). RISC processors are normally found only in high-end (expensive) workstations. See CISC.

RLOGIN

Remote Login: a service on internets very similar to TELNET. RLOGIN was invented for use between Berkeley Unix systems on the same LAN at a time when TELNET programs didn't provide all the services users wanted.

router

A special-purpose dedicated computer that attaches to two or more networks and routes packets from one network to the other. In particular, an Internet gateway routes IP datagrams among the networks it connects. Gateways route packets to other gateways until they can be delivered to the final destination directly across one physical network.

server

A computer that shares its resources, such as printers and files, with other computers on the network. An example of this is a Network Files System (NFS) Server which shares its disk space with a workstation that does not have a disk drive of its own.

SLIP

Serial Line Internet Protocol.

SMTP

Simple Mail Transfer Protocol: the Internet standard protocol for transferring electronic mail messages from one computer to another. SMTP specifies how two mail systems interact and the format of control messages they exchange to transfer mail.

SNA

System Network Architecture: IBM's data communications protocol.

SNMP

Simple Network Management Protocol: The SNMP (RFC 1157) is the Internet's standard for remote monitoring and management of hosts, routers, and other nodes and devices on a network.

subnet

A portion of a network, which may be a physically independent network, which shares a network address with other portions of the network and is distinguished by a subnet number. A subnet is to a network what a network is to an internet.

subnet number

A part of the Internet address which designates a subnet. It is ignored for the purposes of Internet routing, but is used for intranet routing.

SURANET

Southeastern Universities Research Association Network: an NSFNET regional network.

T1

A term for a digital carrier facility used to transmit a DS-1 formatted digital signal at 1.544 megabits per second.

T3

A term for a digital carrier facility used to transmit a DS-3 formatted digital signal at 44.746 megabits per second.

TCP

Transmission Control Protocol: a transport layer protocol for the Internet. It is a connection-oriented, stream protocol defined by RFC 793.

TCP/IP

Transmission Control Protocol/Internet Protocol: this is a common shorthand which refers to the suite of application and transport protocols which run over IP. These include FTP, Telnet, SMTP, and UDP (a transport layer protocol).

TCS

TCS, the Washington Apple Pi user group computer bulletin board and Internet service. The TCS consists of a network of Apple IIgs and Macintosh computers linked together via a unique mixture of network topologies and protocols, and connected to the outside world over an ISDN line. Once upon a time, TCS meant "telecommunications service," but no one admits to being old enough to remember that.

Telenet

A public packet-switching network operated by US Sprint.

TELNET

The Internet standard protocol for remote terminal connection service. Telnet allows a user at one site to interact with a remote timesharing system at another site as if the user's terminal was connected directly to the remote computer.

Token Ring

A type of LAN. Examples are IEEE 802.5, ProNET-10/80 and FDDI. The term "token ring" is often used to denote 802.5.

topology

The physical layout of a network.

Tymnet

A public packet-switching network operated by McDonnell Douglas Network Systems Company.

UDP

User Datagram Protocol: a transport layer protocol for the Internet. It is a datagram protocol which simply adds a level of reliability to IP datagrams. It is defined by RFC 768.

ULTRIX

UNIX-based operating system for Digital Equipment Corporation computers.

UNIX

An operating system developed by Bell Laboratories that supports multiuser and multitasking operations.

UUCP

UNIX-to-UNIX Copy Program: a protocol used for communication between consenting UNIX systems.

VMS

Virtual Memory System: a Digital Equipment Corporation operating system.

WAIS

Wide Area Information Server: an Internet service for looking up specific information in Internet databases.

WAN

Wide Area Network.

WESTNET

One of the National Science Foundation funded regional TCP/IP networks that covers the states of Arizona, Colorado, New Mexico, Utah and Wyoming.

WHOIS

An Internet program which allows users to query a database of people and other Internet entities, such as domains, networks, and hosts, kept at the NIC. The information for people shows a person's company name, address, phone number and email address.

WWW

World Wide Web. You are looking at a World Wide Web document.

X.25

A data communications protocol developed to describe how data passes into and out of public data communications networks. The public networks such as Telenet and Tymnet use X.25 to interface to customer computers.