[an error occurred while processing this directive]

Select here to browse the glossary. . . .


Table of Contents


Browse the Glossary. . . .

Apple Remote Access (ARA)

Apple Remote Access allows Macintosh computers to communicate with AppleTalk networks via modem. This allows remote machines -- that is, Macintoshes that are not directly wired to an AppleTalk network with LocalTalk or Ethernet cables -- to establish a client-server modem link (as opposed to a dumb-terminal modem link) with servers on the network, thus allowing the user to run client software through a telephone connection.

[ Table of Contents ]

AppleTalk

AppleTalk allows Macintosh computers that are networked to communicate among themselves. It is a network protocol that is built directly into the Macintosh and which serves Macs that are connected to a network with LocalTalk or Ethernet cables. Macs that are linked to the AppleTalk system can use client programs in a client-server relationship (as opposed to a dumb-terminal relationship) with servers on the network.

[ Table of Contents ]

Archie

Archie is a search program designed to locate software on the Internet that is available for FTP. Given the name of a program -- or given a keyword that specifies a general category of programs -- Archie will ask the different software providers on the Internet to send information on any programs that match the name or keyword. This information includes the FTP address and file path, which guide users who want to download software files into their own accounts or onto their own computers.

[ Table of Contents ]

ASCII File

Unlike binary files, an ASCII file is a file that is stored in clear text; that is, it is a file which humans can read. ASCII stands for American Standard Code for Information Interchange, which defines a method for representing the alphabetic, numeric, and control characters used in computer communications and coded in hexadecimal notation.

[ Table of Contents ]

Binary File

Binary files are generally executable programs or files used by application software, coded in binary form. Binary files are distinguished from ASCII files, which store straight-text information.

[ Table of Contents ]

BITNET

BITNET is a computer network made up primarily of IBM mainframe computers. BITNET system names often include the letters VM, which is the name of the operating system used on most BITNET servers -- for example, YaleVM, a BITNET server at Yale. BITNET originated at Yale in the 1970s and, technically, is distinct from the Internet; however, most BITNET systems are now directly connected to the Internet.

[ Table of Contents ]

Bulletin Board System (Usenet Newsgroups)

Bulletin Board Services -- commonly called BBS's, Usenet Newsgroups, or just newsgroups -- are among the most popular features of the Internet. Bulletin boards are news repositories where users can read or post the latest on an enormous range of topics: humor, politics, sports, computers, Star Trek, history, literature, cycling, weather, and much more.

[ Table of Contents ]

Client-Server Model

A client is a computer or process that relies on the resources of another computer or process -- that is, on the resources provided by a server. A "client program" is software that resides on a client computer and uses the resources provided by a server. For example, a client program such as the Eudora email package contacts a network mail server in order to request email services, and the network mail server responds to this request by offering those services. The client-server model is distinguished from dumb-terminal network operations and is superior to the dumb-terminal model for several reasons. First, the client-server model better utilizes the resources of the computer a user is sitting before; client software is actually loaded on the client computer and uses the features of the client computer: a graphical interface, mouse, pull-down menus, and so forth. In dumb-terminal usage, the computer a user is sitting before only displays the work that a network computer located elsewhere does on the user's behalf. This often makes network operations performed in a client-server environment feel more "familiar" than those performed in a dumb-terminal environment. Second, client-server operations put less strain on networks than dumb-terminal operations because client software handles much of the information-processing on the client computer itself rather than on the server. Third, and for the same reason, users can perform many network tasks most efficiently in a client-server environment because these tasks will be performed faster on a client computer than on a server, which will often suffer slowdowns when network usage is heavy.

At Yale, client-server service is offered to users with direct connections to the network via LocalTalk or Ethernet wiring and to users who use modems to access SLIP or Apple Remote Access accounts. When users access the network through their Minerva/Pantheon accounts or through the MPG (Multi-Protocol Gateway) -- generally when dialing in with communications software like Kermit (PCs) or TinCan (Macintoshes) -- then they are using dumb-terminal connections.

[ Table of Contents ]

Compression

Compression techniques reduce the amount of storage or bandwidth that information demands without altering the contents of the information. Files transferred over the network -- those requested from FTP sites, for example -- are often stored in various compressed formats and must be decompressed before being usable. Certain kinds of dialin connections also use compression methods to make network operations more efficient.

[ Table of Contents ]

CSO Phone Books

The CSO nameserver is an online directory developed at the University of Illinois and used widely by educational institutions around the world to provide directory assistance. The Yale online directory is a CSO system. All CSO directories are available throughout the Internet -- meaning, for example, that Internet users at the University of Illinois can browse Yale's online directory and that Internet users at Yale can browse the directory at Illinois.

[ Table of Contents ]

Dialup Services

Dialup connections establish links between computers via a telephone line, usually by means of a modem and an appropriate communications software package. Dialup services at Yale can utilize either the client-server or the dumb-terminal model. SLIP and Apple Remote Access accounts provide the user with client-server access; all other dialin accounts at Yale rely on the dumb-terminal model.

[ Table of Contents ]

Discussion Groups

Discussion groups are forums for exchanging information about a topic by electronic mail. Online discussions take place in the following way: a user who has subscribed to the group will send a message to the group address, then the message will be redistributed through email to every member of the group. Messages arrive in a subscriber's email inbox, just as personal letters from friends and colleagues do. Many online discussion groups are integrated into the Listserv system, which is an organizational structure that supports several thousand discussion groups.

[ Table of Contents ]

Domain Name

The domain name is an Internet addressing convention. Email addresses on the Internet generally have the following form: userid@domain_name. All the information to the right of the @ sign is the domain name. (The domain name for Minerva, for example, is minerva.cis.yale.edu.)

[ Table of Contents ]

DOS

DOS, or MS-DOS, is the operating system Microsoft Word developed for the IBM PC. It provides PCs and PC-compatibles with their basic instructions for using and storing files; communicating with networking ports, printers, disk drives, monitors, and modems; and organizing the computer's memory. In the broadest sense, DOS allocates the computer's resources.

[ Table of Contents ]

Dumb-Terminal Model

The dumb-terminal model describes the situation where a local terminal or computer connects to a remote computer and relies on the remote computer to provide the computing and informational resources needed for the work session. The local unit is limited to displaying characters on the monitor and providing characters via the keyboard; it is the remote computer that does the overwhelming majority of the work in dumb-terminal sessions.

The dumb-terminal model is distinguished from client-server network operations and is inferior to the client-server model for several reasons. First, the client-server model better utilizes the resources of the computer a user is sitting before; client software is actually loaded on the client computer and uses the features of the client computer: a graphical interface, mouse, pull-down menus, and so forth. In dumb-terminal usage, the computer a user is sitting before only displays the work that a network computer located elsewhere does on the user's behalf. This often makes network operations performed in a client-server environment feel more "familiar" than those performed in a dumb-terminal environment. Second, client-server operations put less strain on networks than dumb-terminal operations because client software handles much of the information-processing on the client computer itself rather than on the server. Third, and for the same reason, users can perform many network tasks most efficiently in a client-server environment because these tasks will be performed faster on a client computer than on a server, which will often suffer slowdowns when network usage is heavy.

At Yale, client-server service is offered to users with direct connections to the network via LocalTalk or Ethernet wiring and to users who use modems to access SLIP or Apple Remote Access accounts. When users access the network through their Minerva/Pantheon accounts or through the MPG (Multi-Protocol Gateway) -- generally when dialing in with communications software like Kermit (PCs) or TinCan (Macintoshes) -- then they are using dumb-terminal connections.

[ Table of Contents ]

Electronic Mail (E-mail)

Electronic mail is the most popular of all network services -- a quick, inexpensive way to send messages across the street or around the world. There are numerous programs available to help you compose, read, send, and receive email; these include Pine, Elm, Eudora, QuickMail, Berkeley Mail, xmail, mh, and many others. Academic Computing Services (ACS) supports Pine and Eudora.

[ Table of Contents ]

Ethernet

Ethernet is a system of cables and communication protocols that allow computers to be linked in network. Both fast and cheap, Ethernet is the most common way to hook PCs and PC-compatibles into networks. When Macintoshes are connected to Ethernet -- sending AppleTalk via Ethernet -- they are called EtherTalk networks.

[ Table of Contents ]

FAQ

FAQ is the abbreviation for Frequently Asked Questions. Many online help programs throughout the Internet contain a file called FAQ or Frequently Asked Questions. Read the FAQ's! These files contain the collected wisdom users, programmers, consultants, and network administrators have gathered over the years. FAQ's don't always make for the most entertaining reading, but they do hold invaluable information for users who are trying to find their way around the network.

[ Table of Contents ]

Finger

The finger command allows a user to gather information about network users who have accounts on either a local or a remote server that uses the Unix operating system. There are two primary ways to use finger. First, you can use it to determine who is logged on to a system at a given time. And, second, you can use finger to find information (such as the user's login name and real name, directory and account information, the amount of idle time if the user is currently logged on, and two optional memo areas which offer more personal information) about an individual who has a network account.

[ Table of Contents ]

Free-Net

A free-net site is a server, running Free-Net software developed at Case Western Reserve University, that provides community based, public-access networking services to the general public. Free-net sites offer networking resources -- often very limited, but occasionally quite expansive -- free of charge.

[ Table of Contents ]

Freeware

Freeware is computer software that is made available to users free of charge. An enormous number of freeware programs are available for downloading off the network -- locally off the freeware/shareware file servers available at Yale, or throughout the Internet via anonymous FTP.

[ Table of Contents ]

FTP (File Transfer Protocol)

File Transfer Protocol, commonly called FTP, is a set of procedures that allows network users to transfer files between computers. Software, documents, pictures, data sets, sounds, movies: an enormous range of files can be moved through the global network from computer to computer. FTP emerged from the need to transfer files between computers that possessed greatly differing hardware and software resources; in principle, it is meant to be a hardware-independent and software-independent protocol.

A common way to transfer files is by "anonymous FTP" -- which allows the user to log on to a server as a guest and download files stored on the server. Anonymous FTP is an important development because it permits users to download files stored on servers where they do not have accounts.

[ Table of Contents ]

GIF (Graphical Interchange Format)

GIF is a format, first developed by the CompuServe commercial network but now widely available throughout the Internet, for encoding high-resolution graphics in computer files.

[ Table of Contents ]

Gopher

Gopher is a simple yet powerful system of menus that helps network users venture out into the Internet and find resources for fun and work. It works by presenting the user with a series of choices listed in a menu format, awaiting the user's choice, then producing the result of that choice -- perhaps another menu with more choices that offer a chance to narrow down the search, perhaps a document, perhaps a search program, perhaps a data file. Gopher also serves as a "document delivery" system, providing tools for downloading files to a user's own account or computer.

Along with the World Wide Web, the Gopher system is one of the two most useful browsing tools available for locating and using the many resources scattered throughout the Internet. Currently, more than 5,000 sites are maintaining Gopher sites for the global community of Internet users.

[ Table of Contents ]

GUI (Graphical User Interface)

GUI's, sometimes pronounced gooooo-eeez, are programs that use on-screen images (such as windows, menus, scroll bars, buttons, and dialog boxes) and peripheral devices (such as a mouse or trackball) to present information and to make the software usable. The Macintosh uses a GUI, as do PCs that run Windows.

[ Table of Contents ]

Host Computer

A host is a computer or computer system that is located on a network. A host name is the designation for a host computer, as specified within the full domain name for a particular domain. For instance, the full domain name for Minerva is minerva.cis.yale.edu; the host name is "minerva".

[ Table of Contents ]

HTML (Hypertext Markup Language)

HTML is a set of conventions that can be written into text files in order to make the files readable within the World Wide Web hypertext system. HTML gives the user a chance to format documents for the World Wide Web, and also to establish links between files or between different sections of the same file. Text files that have been "marked up" with HTML can link up with files containing text, data, visual images, sounds, and motion pictures.

[ Table of Contents ]

Hypertext

A hypertext document is a text file that includes links to other files, files files containing text, data, visual images, sounds, or motion pictures that "lie behind" the document. According to hyptertext conventions, "hot links" within a document will appear as highlighted expressions (underlined, bold face, unique color, italicized); this indicates that these expressions will point to (link up with) another file, when selected.

[ Table of Contents ]

Interchange Format (RTF)

The Interchange Format, or Rich Text Format (RTF), was designed to help make word-processing files readable by word-processing programs other than the one the file was written with. A document written in Microsoft Word can be saved as an RTF file (check out the File Format option), then will be readable in any other word-processing program with a suitable RTF translator. RTF is especially useful for sending and receiving documents over the network because it preserves both the text and the formatting information that make up a normal word-processing document.

[ Table of Contents ]

IP (Internet Protocol)

The Internet Protocol specifies how packets of information are sent across a communications network. Together, the Internet Protocol and the Transmission Control Protocol (TCP/IP) define a general set of rules for formatting and routing packets of information from one network device to another.

[ Table of Contents ]

Kermit

The word Kermit is a semantics nightmare in the world of the Internet. It indicates either of two separate things. On one hand, Kermit is a protocol for transferring files -- a protocol available on Minerva/Pantheon's UNIX operating system, a protocol available on many communications software packages designed for modem use (Kermit is available on TinCan, a communications package for Macintoshes, for instance), a protocol whose use is widespread indeed. On the other hand, however, Kermit (really, MS-Kermit) is also a communications software package. In fact, just to make sure everything is as confusing as possible, it is a communications package that supports file transfers using the Kermit protocol.

At Yale, this confusion is particularly acute because the use of the Kermit communications package is very common. It is available free of charge off the Yale network, and it is the communications package for the PC that the Acadameic Computing Services department supports. In general, though, the essential point to remember is that the word Kermit refers to two things: a protocol for file transfers and a communications software package.

[ Table of Contents ]

LAN (Local Area Network)

A Local Area Network is a network that connects computers in a relatively small area -- a room, a building, or a set of buildings -- with transmission media such as coaxial cables or twisted-pair wiring.

[ Table of Contents ]

Listserv

Listserv is an Internet facility that maintains a large number of electronic mailing groups -- also called discussion groups. Electronic mailing groups are forums for exchanging information about a topic by email. These online discussions take place in the following way: a user who has subscribed to the group will send a message to the group address, then the message will be redistributed through email to every member of the group. Messages arrive in a subscriber's email inbox, just as personal letters from friends and colleagues do.

[ Table of Contents ]

Mercury

Mercury, along with Minerva and Morpheus, is one of the Yale network computers that sustains the Minerva/Pantheon account system. Network users can log into any of the three machines in order to access their Yale accounts. It is recommended that users log in to the machine that shows the lowest "load average" (the welcome screen discloses the "load average" when users log on to Minerva/Pantheon).

[ Table of Contents ]

Minerva/Pantheon

Minerva, along with Mercury and Morpheus, is one of the Yale network computers that sustains the Minerva/Pantheon account system. Network users can log into any of the three machines in order to access their Yale accounts. It is recommended that users log in to the machine that shows the lowest "load average" (the welcome screen discloses the "load average" when users log on to Minerva/Pantheon).

Yale's network account system is called "Minerva/Pantheon" because Minerva was the first of the three gods to have a machine named after her.

[ Table of Contents ]

Modem

Modem stands for modulator-demodulator; it is a device that converts data to a form that can be transmitted (usually by telephone) to data-processing equipment, where a similar device reconverts it and then processes it. In plain English, it is a device that either sits next to a computer (i.e., external modems) or inside a computer (i.e., internal modem) that makes it possible for computers to communicate with one another over telephone lines.

[ Table of Contents ]

Morpheus

Morpheus, along with Minerva and Mercury, is one of the Yale network computers that sustains the Minerva/Pantheon account system. Network users can log into any of the three machines in order to access their Yale accounts. It is recommended that users log in to the machine that shows the lowest "load average" (the welcome screen discloses the "load average" when users log on to Minerva/Pantheon).

[ Table of Contents ]

Nexis

Nexis is an online news service that provides access to the full text of more than 650 information sources -- newspapers, magazines, newsletters, and broadcast transcripts. News abstracts are available for more than 1,000 additional sources.

[ Table of Contents ]

ph (Directory Lookup)

The ph (Directory Lookup) service queries the CSO nameserver -- an online database of university students and staff at Yale and beyond -- in order to provide the following information (more or less) about an individual: the complete name, telephone number, postal address, email address, and year in school.

[ Table of Contents ]

PPP (Point-to-Point Protocol

PPP is a communications protocol used over serial lines that allows computer users to connect to a network and establish a client-server relationship (as opposed to a dumb-terminal relationship). It is most common to run PPP over telephone lines, through a modem. PPP allows users to employ client software with a telephone connection, replicating (albeit at much lower speeds) almost all of the functionality of a network connection running over LocalTalk or Ethernet cables.

[ Table of Contents ]

Shareware

Shareware is computer software that is made available to users at a much lower price than commercial vendors would normally charge. An enormous number of shareware programs are available for downloading off the network -- locally off the freeware/shareware file servers available at Yale, or throughout the Internet via anonymous FTP.

[ Table of Contents ]

SLIP (Serial Line Internet Protocol)

SLIP is a communications protocol used over serial lines that allows computer users to connect to a network and establish a client-server relationship (as opposed to a dumb-terminal relationship). It is most common to run SLIP over telephone lines, through a modem. SLIP allows users to employ client software with a telephone connection, replicating (albeit at much lower speeds) almost all of the functionality of a network connection running over LocalTalk or Ethernet cables.

SLIP service is currently being phased out at Yale, in favor of PPP.

[ Table of Contents ]

TCP (Transmission Control Protocol)

TCP is a protocol used over the Internet Protocol (IP), offering reliable transmission of data between computers and computer systems. Together, the Transmission Control Protocol and the Internet Protocol (TCP/IP) define a general set of rules for formatting and routing packets of information from one network device to another.

[ Table of Contents ]

TCP/IP (Transmission Control Protocol over Internet Protocol)

Together, the Transmission Control Protocol and the Internet Protocol (TCP/IP) define a general set of rules for formatting and routing packets of information from one network device to another. It is TCP/IP that makes it possible to use Telnet, FTP, electronic mail, and many other services among the computers within a heterogeneous network.

[ Table of Contents ]

Telnet

Telnet is a connection protocol that allows users to work on a computer somewhere else -- just a few steps away, or across the globe -- through any networked computer that has access to the Internet's telnet facility. Telnet is the standard protocol that lets users log on to a remote host computer; it gives the logged-on user access to the informational and computing resources of the remote host.

[ Table of Contents ]

Terminal Emulation

Terminal emulation is a process whereby a computer acts like a specific kind of terminal when another computer contacts it. This process emerged as a response to the great variety of protocols different computers and terminals use for encoding, sending, receiving, and presenting information. Two common families of emulations are the VT series and the 3270 series, developed by Digital Equipment Corporation and IBM, respectively, for use with their mainframes. At Yale, the VT100 terminal emulation (or "terminal type") is currently able to handle most network emulation needs.

[ Table of Contents ]

tn3270

This is a version of the Telnet program, designed specifically for remote logins to IBM mainframe computers that use the 3270 terminal emulation. Telnet is a connection protocol that allows users to work on a computer somewhere else -- just a few steps away, or across the globe -- through any networked computer that has access to the Internet's telnet facility. Telnet is the standard protocol that lets users log on to a remote host computer; it gives the logged-on user access to the informational and computing resources of the remote host.

[ Table of Contents ]

Unix

Unix is an operating system, developed at Bell Laboratories and modified at the University of California at Berkeley, which was used extensively in the early development of Internet protocols. Unix is a multi-user, multitasking operating system that is quite common, found throughout the Internet. At Yale, the Minerva-Mercury-Morpheus cluster of machines, which supports the Minerva/Pantheon account system, runs Unix.

[ Table of Contents ]

URL (Uniform Resource Locator)

URL is the addressing scheme that has been developed to organize materials on the World Wide Web.

[ Table of Contents ]

Veronica

Veronica is a search program that helps users find items contained within the Gopher system -- within GopgerSpace, that is.

[ Table of Contents ]

VT100

VT100 is the terminal emulation (or "terminal type") that most of the network services at Yale use. It is a common form of terminal emulation using communications protocols developed for the VT100 terminal from Digital Equipment Corporation.

[ Table of Contents ]

WAIS (Wide Area Information Server)

WAIS (pronounced "ways") stands for Wide-Area Information Servers. It is an index of the contents of more than 500 databases on the Internet; when a user employs WAIS, it searches its index and tries to match the search-request you have entered with the information that is available in its index. Although the majority of the Internet's most useful resources cannot yet be searched through WAIS, it is becoming increasingly clear that WAIS is one of the technologies future network database developments will have to accommodate.

[ Table of Contents ]

WAN (Wide Area Network)

Wide Area Networks, as opposed to Local Area Networks, are designed to cover large geographic areas.

[ Table of Contents ]

World Wide Web (WWW)

World Wide Web -- WWW, W3 -- is a hierarchical hypertext system designed to allow network users to navigate the Internet in a simple, relatively painless manner. It works by presenting the user with hypertext documents, documents that include some highlighted text. The user then selects a highlighted text, and this will call up another file that elaborates on the highlighted text in the previous document. Users navigate through the Internet by selecting the highlighted texts, considering the elaborations of those texts, and selecting further elaborations until they reach their destination.

Common programs used for browsing the World Wide Web include Netscape and Mosaic on PCs and Macintoshes, and Lynx from within Minerva/Pantheon.

[ Table of Contents ] [an error occurred while processing this directive]