Traveling the Electronic Highway: Glossary

Maps, Encounters, Directions.

Master Copy on Earth.
Started January 1998

© Gio Wiederhold 1997

Terms relevant to Internet Computing

Format is TERM: definition. Click on ¶ to go to the relevant section in a book chapter.

A

Address: in communication, the part of the message containing the destination; in computing, the identifier of a word in memory.
Aloha-net: an early satellite WAN for the Hawaiian islands.
Anthropometric: See Biometric
API: Application Program Interface. HREF="ubi"
Applets: tiny programs, typically written in Java, that are loaded as part of web-responses and use the client computer's resources to carry out their work. They are normally restricted from modifying files on the hard disk, etc.
ARPA: Advanced Research Projects Agency of the U.S. Defense department, see DARPA.
ATM (Asynchronous Transfer Mode): technology for high-speed backbone service
Attack: attempts by hackers to break through computer security systems or disable computer operations.
Authentication: verification that that a potential customer is indeed the person or institutional unit they purport to be, may involve passwords or biometric devices ¶.
Attention: the time that a reader gives to peruse presented information. Valued by advertisers and the like.
Authorization: giving a customer or intermediary (proxy) permission to execute programs or receive Information. HREF="security", the customer should be authenticated ¶.
avatar: a virtual personage or perhaps a mythical beast, representing a game player in a MUD.

B

Backbone: The long-range connections for the Internet. Provided by about 10(see).
Back Door: A means to gain rapid entry into a program, typically bepassing login checks. Backdoors are sometimes created for debugging, intendended to be removed before product release, but sometimes forgotten, or may be created by a virus. Use of a back door makes reentry easy--and difficult to detect.
Bandwidth: measure of maximal data transmission capability, in bits/second.
Beans or JavaBeans: run-time invokable component services HREF="ubi".
Biometric: measures to authenticate individuals depending on their biological uniqueness, as signatures, fingerprints, iris patterns, DNA, etc. ¶
Bit: atomic data-value, may be 0 or 1.
Black-hat hackers: Joyriders on the Net. They get a kick out of crashing systems, stealing and distributing passwords, and generally wreaking as much havoc as possible.
Broadcast: transmission of a message to anyone reachable.
Browsers: programs that help in obtaining multi-media data from remote nodes, following the HTTP protocol.
Buffer: an area in computer memory to hold data or instructions. Buffers are often neeeded to hold information from disk or communication lines that have their own speed control, and cannot be directly synchronized with Processing
Buffer overflow: a computer program error condition where more space is used for some task or data than intended and available. Programs should check for, and prevent buffer overflow, but sometimes fail to do so, perhaps because of the processing cost. A virus may use buffer overflow to place malicious code iunto the system, gaining control or crashing a computer
Bulletin board: a file on a node accessible by many customers for the posting and perusal of messages.
Byte: an 8-bit unit, used to transmit a single character or part of a longer unit, as a word, a program instruction (typically 2,3,4 bytes), or an image (thousands of bytes).

C

Checksums: a technique for validatiing that a unit of transmitted or stored data has not been altered ¶.
Clearance: assignment of a security level for mandatory security: primarily in the military.
COM: Microsoft software component objects Component: a separable portion of a large computer program or system.
Computer: hardware which contains at least one processor, and means for input, output, and storage of data.
Computing: processing using a computer.
Cookie: entry in a customers file, left by a browser interaction, to inform successive browser accesses about prior actionsx
Copyright: conventions and laws that restrict copying and distribution of IP belonging to others.
Copy-and-Paste: selection of text from a GUI display for subsequent insertion into another display area. Compare to drag-and-drop,
Crackers: hackers for hire who break into computer systems to steal valuable information for their own financial gain.
CRT: Cathode Ray Tube: an electronic component used for displays.
Customer: the user of an information system who derives a benefit from its operation.

D

DARPA: Defense Advanced Research Projects Agency of the U.S. Defense department, called ARPA from its inception in 1958-1972 and 1992-1994.
Data: encoded observations, writings, images, voice, etc. stored in a computer or on external storage media for retrieval or processing. ENTEDU.Intro. discretionary
Debugging: searching for errors in programs and their removal. Cannot guarantee that all errors are found.
Denial of Service: This is becoming a common networking prank. By hammering a Web site's equipment with too many requests for information, issued from multiple sources, an attacker can effectively clog the system, slowing performance or even crashing the site. This method of overloading computers is sometimes used to cover up an attack.
discretionary security: based on need-to-know, primarily in the military.
display: screen connected to a computer for presentation of results.
DCOM: Distributed COM debugging: removing errors from computer programs.
discretionary security: based on need-to-know, primarily in the military.
Disk storage: computer storage using magnetic or optical disks, may be fixed (hard) or removable.
drag-and-drop: identifying an object on a GUI and making it available to another displayed process. Compare to copy-and-paste
Dumpster diving: Sifting through a company's unprotected user files or literal garbage to find information to help break into their computers. Sometimes the information is used to make a stab at social engineering more credible.

E

Email (Electronic Mail): textual (mainly) messages shipped among network participants.
Encryption: transformation of a text to make it unreadable b anyone not possessing a decryption key ¶.
Escrow: providing intermediate services in a valuable transaction, by holding goods (or a proxy for the goods) and payments until delivery of both can be guaranteed.
Event: signal that triggers a system to start an operation. HREF="ubi"

F

File: a collection of similar records, handled as a unit by the operating system HREF="db".
Flaming: expressing one's opinion in messages in crude form, often broadcasting or multicasting them.
Floppy disks: economical, removable disk storage.
FTP (File Transfer Protocol): Internet service for transmitting a file of data among nodes.
fungible: item instances are indistinguishable for commercial purposes: as dollar biils, books, CDs.

G

Gateway: a node that serves two networks and forwards messages among them. A gateway may have to do protocol and/or format conversions.
Giga or G: postfix for 10^9 or 1 000 000 000, or for computer quantities 2^30 = 1 073 741 824.
GUI: Graphic User Interface, presentation on a terminal screen, as a windows system, that allows output to be seen, marked for copy-and-paste, insertion of commands and text, and buttons to generate events.

H

Hackers: computer experts who relish displaying their capabilities and power. White-Hat and Black hat hackers challenge computer security.
Header: Information in a packet that specifies the destination, sender, and other parameters.
HTML (HyperText Markup Language): a definition of data formats according to SGML, used for web transmission protocols (HTTP).
HTTP (HyperText Transfer Protocol): rules for locating, accessing, transmitting, and displaying web data.
Hyperlinks: links among independently maintained, possibly remote documents, following the HTTP protocol.
Hypertext: text with embedded links to other texts, possibly remote.

I

Indexing: Creation of lists of term with references to records or web pages containing the index material.
Information: results delivered to a customer that are beneficial, i.e., that can cause decisions to be made, actions to occur, and, in time, the state of the real world to be affected. Creating information typically requires processing of data. A weaker definition encompasses all data that is of interest to the recipient. ENTEDU.Intro.
Input: entry of of data or events into a computer, may use keyboards, communication lines, or devices to read magnetic, electro-optical, or physical media.
Insiders: Employees, disgruntled or otherwise, working solo or in concert with outsiders to compromise the security of corporate systems.
Intellectual property (IP): documents on paper or in digital form for which ownership is asserted, by Copyright, Patents, or Trade Secret.
Internet: wide-area communication service.

Internet Service providers (ISPs): companies providing services to end customers, both information comsumers and most, smaller, information providers. They collect monthly and/or incremental service fees, and pay backbone service providers for bandwidth to and from remote sites that they cannot service themselves.

J

Junkmail: messages that have not been requested, and do not provide information.

K

Key: a sequence of characters or bits needed to login or transform a message to plaintext .
Kilo or K: postfix for 1000, or for computer quantities 2^10 = 1024.
Knowledge: rules about processing, for computing must be explicitly or implicitly (in a program) encoded to drive a computation. ENTEDU.Intro.

L

Link: in networks, a communication path between two nodes, may use cable or radio; in documents, a processable cross-reference within or among documents, as a hyperlink.
Local area network (LAN): a communication network under local control, using owned cables or fiber, typically constrained to a university or a factory. Multiple LANs may be connected by gateways. Beyond those boundaries a Wide Area Network is needed.
Logic Bombs: An instruction in a computer program that triggers a malicious act. Can be set to go off at a later day or event
Login (or Logon): starting a session on one's computer, requires authentication unless only local and personal services are made available.
Logoff: termination of a session, costs may be computed and presented.

M

Maintenance: efforts expended for debugging, adjusting to changes in hardware, communication, standards, and/or customer expectations. HREF="mediators"
Mandatory security: based on level of clearance, primarily in the military.
Markup: annotation of documents to provide information about formatting or linkages.
Mediators; value-added software to convert output diverse, autonomous data resources to information for application programs. HREF="mediators"
Mega or M: postfix for 10^6 or 1 000 000, or for computer quantities 2^20 = 1 048 576.
Memory: fast, but volatile area for keeping data and programs.
Message: a unit of transmission, as created by email, containing text and possibly other insertions, with a designation of recipients, source, subject, etc. Mat require multiple packets.
Metadata: data that describe the content, extent, and format of other, primary data collections.
multicast: transmission of a message to a group of recipients, identified by a list of addresses or some feature.
Multi-media: data including text, images, voice encodings, video, and the like.
Multi-programming: ability to handle multiple processes.
Multi-User Dungeons (MUD): virtual game worlds, with avatars.

N

Name servers (DNS): Internet nodes that are designated to look up IP addresses for node names.
Need-to-know: criterium for discretionary security, primarily in the military.
Netiquette: informal rules of behavior for users of networks, as for email.
Network: a communication infrastructure, having nodes and links among them.
NIC: Network Interface Computer, a processors at a network node that interprets the header in order to direct the forwarding of packets along the best route to the proper destinations.
Node: a source, destination, or intermediate station in a communication network, typically with computing capability.

O

Object: a grouping of data about a real-world item or abstract concept. HREF="ubi". Precise scope and implementations differ greatly.
Off-ramp: a computing node where useful processing can take place.
Overloading: the use of a term or the name of a method for more than one purpose, based on context.
Oversubscribing: transmission vendors selling more aggregate bandwidth than they have or are purchasing from higher tier or backbone providers, counting on fractional usage and staistical distribution.

P

Packet: unit of Internet transmission, containing from a few dozen to several hundred bytes, with a machine-processable address for forwarding to the destination node.
Partnership arrangements
Password crackers: Software that guesses passwords, perhaps by transforming login names, from lists of common first names, a dictionary, or dumpster diving.
Peering: backbone service exchange of information transmission without mutual accounting and reimbursement. Also called free peering, to distinguish from paid services, paid peering, imposed on transmission service providers not part of the upper tier of transmission providers. peering does not apply to ISPs.
Peta or P: postfix for 10^15 or 1 000 000 000 000 000, or for computer quantities 2^50 = 1 125 899 906 842 624.
Plaintext: readable, i.e., unencrypted or decrypted text or other information.
Privacy: keeping personal or institutional data or information out of the view of others, who are not specifically authorized.
Process: an execution of a program. While a single processor may have only one active process at a time, a multi-programmed processor may handle many candidate process threads for potential execution.
Processing or data processing: moving or transforming data to add value, often with the intent to create information.
Processor: computer hardware unit able to handle an active process. HREF="ubi"
Program: a sequence of program instructions, that, when interpreted, can control a computer. HREF="ubi"
Program instruction: a single command, placed in memory for execution by a computer processor.
Protocol: in communication the rules that determine when to send what, and how to respond to good and bad transmissions.
Proxies: programs that stand in for other programs.

Q

QoS (Quality-of-Service): measures of performance and system reliability.

R

Redundancy: data or information which duplicates other data or information, but is useful to improve performance or for recovery from errors.
Requests For Comments (RFC): Specifications for Internet protocols and services.
Routers = highly specialized computing processors which link the transmission capabilities of subnets together. See NICs.

S

Scalability: the capability of a network or computer system to accommodate growth without major redesign or rework. Growth includes the number of customers, the number of nodes, and the number and types of services being provided, as well on-going modernizations of hardware, software, and standards.
Scans: Widespread probes of the Internet to determine types of computers, services, and connections. That way the bad guys can take advantage of weaknesses in a particular make of computer or software program.
Scope: the range of applicability of a term. When the term refers to data, it encompasses all the recorded instances.
Scripts: Instructions for invoking sequences of typically small programs.
Script bunnies: Wannabe hackers with little technical savvy who download scripts that automate the job of attacking computers.
Security: the protection of data and information from destruction or improper or inadvertent release. Encompass protection of privacy. HREF="security"
Session: period of computer use, starting with a login and terminating with logoff or failure. May invoke many programs.
SGML (Standard Graphic Markup Language): a protocol to specify markups.
Sniffer: Programs that covertly search individual packets of data as they pass through the Internet, capturing passwords or the entire contents.
Social engineering: A tactic used to gain access to computer systems by talking unsuspecting company employees out of valuable information such as passwords.
Spider: Software to automatically access web pages and collect information for web indexing.
Spoofing: Faking an e-mail address or Web page to trick users into passing along critical information like passwords or credit-card numbers.
Storage: area in a computer for persistent data and programs. See also disk storage.
Supercomputers: large computers, able to handle complex, mainly numerical, computations, operated by service centers.
Synonyms: Two terms used for the same concept. Often synonym use depends on context, and often apparent synonyms have somewhat different scope.

T

Tera or T: postfix for 10^12 or 1 000 000 000 000, or for computer quantities 2^40 = 1 099 511 627 776.
Threads: identifiers of a process, to enable a processor to control, i.e., start, stop, reactivate a process
time-sharing: letting a resource as memory or a communication path be used by multiple programs or messages through frequent cyclic assignment.
Trojan Horse: A program that looks legitimate, but that, unknown to the user, contains instructions that exploit a known vulnerability in some software. It could send out a virus or participate in a denial of service attack.

U

V

Virtual memory: computer memory extension to storage, to overcome limits of the actual hardware memory. HREF="ubi"
Virus: a program that sends replicates out of itself to other sites, typically hidden in innocuous programs or attachments.

W

War Dialing: automatically dialing thousands of telephone numbers in search of a modem connection, followed by a security attack.
Watermarking: a technique for authentication of documents ¶.
web (or World-Wide-Web, WWW): the collection of networks that are reachable through Internet protocols.
White-Hat Hackers: relatively good guys who get turned on by the intellectual challenge of tearing apart computer systems to improve computer security.
Wide Area Networks (WAN): communication networks that extend beyond single geographical units, typically requiring transport over public transmission paths. Often used to connect Local Area Networks via a gateway.
Word: the smallest addressable unit in memory, often equal to a byte.
worm: a program that initiates its execution at a remote computer site.
WWW (World Wide Web): see web.

X

XML (eXtended Markup Language): a definition of data formats with specifications that can be reliably interpreted, see HTML.

Y

Z

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