Glossary of Information Security-Related Terms

Please note that the following glossary is by no means all-inclusive. It has been based on the Information Security Orientation presentations given starting July 2001, and has since been enhanced by customer feedback. This page should be thought of as an on-going work-in-progress. Please see the end of the document for the Internet references used to build this glossary or for information on how to submit an entry to the glossary.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z


** A **

abuse, computer
The willful or negligent unauthorized activity that affects the availability, confidentiality, or integrity of computer resources. Computer abuse includes fraud, embezzlement, theft, malicious damage, unauthorized use, denial of service, and misappropriation. {see also: fraud, computer}

The ability and means to communicate with or otherwise interact with a system in order to use system resources to either handle information or gain knowledge of the information the system contains. Also, the privilege to use computer information in some manner.

The property that enables activities on a system to be traced to individuals who may then be held responsible for their actions. It requires an authentication system (to identify users) and an audit trail (to log activities against users). {see also: availability, confidentiality, integrity}

active attack
See attack

administrative security
The management constraints and supplemental controls established to provide an acceptable level of protection for data.

Any software application in which advertising banners are displayed while the program is running; applications include additional code that delivers the ads, which can be viewed through pop-up windows or through a bar that appears on a computer screen.{see also: spyware}

An attempt to subvert or bypass a system's security, which may or may not be successful.

- Active vs. passive: An "active attack" attempts to alter system resources or affect their operation. A "passive attack" attempts to learn or make use of information from the system but does not affect system resources.

- Insider vs. outsider: An "insider attack" is an attack initiated by an entity inside the security perimeter (an "insider"), i.e., an entity that is authorized to access system resources but uses them in a way not approved by those who granted the authorization. An "outsider attack" is initiated from outside the perimeter, by an unauthorized or illegitimate user of the system (an "outsider"). In the Internet, potential outside attackers range from amateur pranksters to organized criminals, international terrorists, and hostile governments.

1) The process of compiling a list of all software and/or hardware installed on one or more PCs. Once the audit has been performed, the data can be analyzed to check for unauthorized software, missing hardware components, etc.

2) The process of compiling a list of all security relevant events. This should include the user causing the event.

audit trail
A chronological record of when users log in, how long they arc engaged in various activities, what they were doing, and whether any actual or attempted security violations occurred.

The process of establishing the legitimacy of a user before allowing access to requested information. During the process, the user enters a name or account number (identification) and password (authentication). {see also: authorization}

The process of determining what types of activities are permitted. Usually, authorization is in the context of authentication. Once a user has been authenticated, the user may be authorized different types of access or activity. {see also: authentication}

The requirement that information and/or services be available to an authorized user on demand. Attacks against the availability of an information resource are called denial of service (DoS) attacks. {see also: accountability, confidentiality, integrity}

** B **

back door
An undocumented way of gaining access to a program, online service or an entire computer system; a hidden computer flaw known to an intruder, or a hidden computer mechanism (usually software) installed by an intruder, who can activate the back door to gain access to the computer without being blocked by security services or mechanisms. Frequently left by rootkits as well as Trojan horses and other forms of malware. Also referred to as a trap door.

A term that describes the amount of information that can be passed through a communications channel in a given amount of time; that is, the capacity of the channel. Bandwidth is usually expressed in '(kilo/mega)bits per second'.

The use of a computer user's unique physical characteristics -- such as fingerprints, voice, and retina -- to identify that user .

Short for binary digit, the smallest unit of data in a computer. A bit has a single binary value, either 0 or 1, and is abbreviated with a small "b".

black hat
A term used to describe a hacker who has the intention of causing damage or stealing information.

A product that connects a LAN to another LAN that uses the same protocol. {see also: gateway, hub, router, switch}

buffer overflow
A buffer is an area of memory used to hold data for processing, and it has a predetermined size based on the hardware platform and the operating system. If the data being placed into the buffer is too large, not checked, and allowed to overflow the buffer, it can have unexpected effects. At best, the excess data is simply lost; at worst, the excess data might overwrite other legitimate data, allowing a cracker to take control of a system or simply crash it.

A unit of data that is eight binary digits (bits) long, and is abbreviated with an upper-case "B". A byte is the unit most computers use to represent a character such as a letter, number, or typographic symbol (for example, "g", "5", or "?"). Byte multiples are based on powers of 2 and commonly expressed as a "rounded off" decimal number. {see also: kilobyte, megabyte, gigabyte, terabyte}

** C **

Data that has been encrypted

An intrusion of security policy, which has the potential of disclosing private system information to an unauthorized user.

compromise, data
A security incident in which information is exposed to potential unauthorized access, such that unauthorized disclosure, alteration, or use of the information may have occurred.

computer abuse
See abuse, computer

computer fraud
See fraud, computer

Computer Fraud and Abuse Act, 18 U.S.C. §1030:
The primary federal anti-hacking statute; criminalizes seven forms of activities:

1) Section (a)(1) prohibits the knowing access of computers to obtain classified information without authorization or in excess of authorization;
2) Section (a)(2) prohibits the intentional access of a computer to obtain information from a financial institution, the federal government, or any protected computer involved in interstate or foreign communications (essentially any computer connected to the Internet) without authorization or in excess of authorization;
3) Section (a)(3) prohibits the intentional and unauthorized access of computers of the federal government, or computers used by or for the government when the access affects the government's use of that computer;
4) Section (a)(4) prohibits the knowing access of a protected computer without authorization or in excess of authorization with the intent to defraud;
5) Section (a)(5)(A) prohibits anyone from knowingly causing the transmission of a program, information, code, or command, and as a result of such conduct, intentionally causes damage without authorization, to a protected computer. Section (a)(5)(B) prohibits the intentional unauthorized access of a computer that recklessly causes damage. Section (a)(5)(C) covers the intentional unauthorized access of a computer that negligently causes damage;
6) Section (a)(6) prohibits the knowing trafficking of computer passwords with the intent to defraud;
7) Section (a)(7) prohibits the transmission of communications containing threats to cause damage to a protected computer.

computer security
Technological and managerial procedures applied to computer systems to ensure the availability, integrity, and confidentiality of information managed by the computer system. Often synonymous with information security.

Computer Security Act of 1987
Requires agencies to identify sensitive systems, conduct computer security training, and develop computer security plans.

computer security incident
See incident, computer security

A requirement that private or confidential information not be disclosed to unauthorized individuals, entities, or processes. Data whose confidentiality has failed is said to be compromised. {see also: accountability, availability, integrity}

confidentiality, data
The property that information is not made available or disclosed to unauthorized individuals, entities, or processes. {see also: integrity, data; security, data}

An action that undesirably alters system operation by adversely modifying system functions or data.

Any action or device that reduces a computer system's vulnerability

Generally considered to be a hacker who has turned to the dark side; that is, a hacker who breaks into other systems with the specific purpose of causing damage or stealing data. A derogative term, it should be used instead of hacker for computer security incidents. {see also: intruder, packet monkey, script kiddie}

The act of breaking into a computer system. {see also: hacking}

Crimeware is any computer program or set of programs designed expressly to facilitate illegal activity online. (more info)

A condition of a service or other system resource such that denial of access to (i.e., lack of availability of) that resource would jeopardize a system user's ability to perform a primary function or would result in other serious consequences. {see also: sensitive (information)}

Protecting information or hiding its meaning by converting it into a secret code before sending it out over a public network.

** D **

data compromise
See compromise, data

data confidentiality
See confidentiality, data

data integrity
See integrity, data

data security
See security, data

decentralized server
See server, decentralized

A circumstance or event that may result in an authorized entity receiving false data and believing it to be true.

demilitarized zone
A computer host or small network inserted as a "neutral zone" between a company's private network and the outside public network. It prevents outside users from getting direct access to a server that has company data. (The term comes from the geographic buffer zone that was set up between North Korea and South Korea following the war in the early 1950s.) A DMZ is an optional and more secure approach to a firewall and effectively acts as a proxy server as well. In a typical DMZ configuration for a small company, a separate computer (or host in network terms) receives requests from users within the private network for access to Web sites or other companies accessible on the public network. The DMZ host then initiates sessions for these requests on the public network. However, the DMZ host is not able to initiate a session back into the private network. It can only forward packets that have already been requested. Users of the public network outside the company can access only the DMZ host. The DMZ may typically also have the company's Web pages so these could be served to the outside world. However, the DMZ provides access to no other company data. In the event that an outside user penetrated the DMZ host's security, the Web pages might be corrupted but no other company information would be exposed.

denial of service (DoS)
The prevention of authorized access to a system resource or the delaying of system operations and functions. {see also: distributed denial of service (DDoS) attack, e-mail bomb}

A circumstance or event whereby an entity gains access to data for which the entity is not authorized.

distributed denial-of-service (DDoS) attack
An attack in which a multitude of compromised systems attack a single target, thereby causing denial of service for users of the targeted system. The flood of incoming messages to the target system essentially forces it to shut down, thereby denying service to the system to legitimate users. {see also: denial of service (DoS)}

See demilitarized zone

dumpster diving
Looking through trash for personal data, access codes, or other sensitive information

** E **

e-mail bomb
Code that, when executed, sends many messages to the same address(s) for the purpose of using up disk space and/or overloading the e-mail or web server. {see also: denial of service (DoS), logic bomb, malicious logic, malware, Trojan horse, virus, worm}

The process of changing data into a form that can be read only by the intended receiver. Encryption is the conversion of data into a form, called a ciphertext, which cannot be easily understood by unauthorized people. Decryption is the process of converting encrypted data back into its original form, so it can be understood.

A threat action whereby sensitive data is directly released to an unauthorized entity.

A computer network that an organization uses to carry application data traffic between the organization and its business partners. {see also: intranet, virtual private network (VPN)}

** F **

A backup operational mode in which the functions of a system component (such as a processor, server, network, or database, for example) are assumed by secondary system components when the primary component becomes unavailable through either failure or scheduled down time.

A system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both. They are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria/policy requirements.

Software (programs or data) that has been written onto read-only memory (ROM). Firmware is a combination of software and hardware. ROM s, PROM s and EPROM s that have data or programs recorded on them are considered firmware.

fraud, computer
Computer-related crimes involving deliberate misrepresentation, unauthorized disclosure, or alteration of data in order to obtain something of value. {see also: abuse, computer}

** G **

A network point that acts as an entrance to another network. {see also: bridge, hub, router, switch}

A measurement of digital data storage or transfer capacity, abbreviated GB. A true gigabyte is equal to a kilo-kilo-kilobyte (1024*1024*1024 bytes) or 1,073,741,824 bytes. This is usually confused with the advertising gigabyte which is only 1,000,000,000 (one billion) bytes.

** H **

A slang term for a computer enthusiast, i.e., a person who enjoys learning programming languages and computer systems and can often be considered an expert on the subject(s). The pejorative sense of hacker is becoming more prominent largely because the popular press has co-opted the term to refer to individuals who gain unauthorized access to computer systems for the purpose of stealing and corrupting data. {see instead: cracker}

Unauthorized use, or attempts to circumvent or bypass the security mechanisms of an information system or network. {see also: cracking}

The act of hacking, or breaking into a computer system, for a politically or socially motivated purpose. The individual who performs an act of hacktivism is said to be a hacktivist.

Refers to objects that you can actually touch, like disks, disk drives, display screens, keyboards, printers, boards, and chips. In contrast, software is untouchable. Software exists as ideas, concepts, and symbols, but it has no substance.

The process of taking over a live connection between two users so that the attacker can masquerade as one of the users.

A common connection point for devices in a network, commonly used to connect segments of a LAN. A hub contains multiple ports; when a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets. {see also: bridge, gateway, router, switch}

** I **

incident, computer security
Any intrusion or attempted intrusion into an information system; incidents can include probes of multiple computer systems.

information security
The result of any system of policies and/or procedures for identifying, controlling, and protecting information from unauthorized disclosure. Often synonymous with computer security.

insider attack
See attack

Those individuals who work for the target organization or have a relationship with the organization that grants the individual some level of access. This includes employees, contractors, business partners, customers, subcontractors, etc.

The assurance that information can only be accessed or modified by those authorized to do so. Data whose integrity has failed is said to be corrupted. {see also: accountability, availability, confidentiality}

integrity, data
The property that data has not been changed, destroyed, or lost in an unauthorized or accidental manner. {see also: confidentiality, data; security, data}

internet vs. Internet
Not capitalized: A popular abbreviation for "internetwork".

Capitalized: "The Internet" is the single, interconnected, worldwide system of commercial, government, educational, and other computer networks that share the set of protocols specified by the Internet Advisory Board. {see also: web vs. Web}

A computer network, especially one based on Internet technology, that an organization uses for its own internal, and usually private, purposes and that is closed to outsiders. {see also: extranet, virtual private network (VPN)}

An entity that gains or attempts to gain access to a system or system resource without having authorization to do so. {see also: ankle-biter, cracker, packet monkey, script kiddie}

Any set of actions that attempt to compromise the integrity, confidentiality, or availability of a resource.

intrusion detection
Detection of break-ins or break-in attempts either manually or via software expert systems that operate on logs or other information available on the network.

intrusion detection system (IDS)
A hardware/software solution that inspects all inbound and outbound network activity and identifies suspicious patterns that may indicate a network or system attack from someone attempting to break into or compromise a system.

intrusion, security
A security event, or a combination of multiple security events, that constitutes a security incident in which an intruder gains, or attempts to gain, access to a system (or system resource) without having authorization to do so.

IP spoofing
An attack where the attacker disguises himself or herself as another user by means of a false IP network address.

** K **

A hardware device or a software application designed to capture user keystrokes. The device or application is usually installed without the user's knowledge, and is used to capture user information (passwords, credit card information, PINs, etc.). The information is later retrieved by the intruder.

keystroke monitoring
The process of recording every character typed by a computer user on a keyboard.

A measurement of digital data storage or transfer capacity, abbreviated KB. A true kilobyte is equal to 1,024 bytes. This is usually confused with the advertising kilobyte which is only 1,000 (one thousand) bytes.

** L **

See local area network

See war driving

An e-mail containing live data intended to cause damage to the recipient's computer. {see also: e-mail bomb}

load balancing
Dividing the amount of work that a computer has to do between two or more computers so that more work gets done in the same amount of time and, in general, all users get served faster. This can be applied to network appliances, as well.

local area network
A group of computers and associated devices that share a common communications line and typically share the resources of a single processor or server within a small geographic area (for example, within an office building or on a campus). Usually, the server has applications and data storage that are shared in common by multiple computer users. A local area network may serve as few as two or three users (for example, in a home network) or many as thousands of users (for example, in a university setting).

The process of storing information about events that occurred on a firewall, network, or server.

logic bomb
Malicious logic that activates when specified conditions are met. Usually intended to cause denial of service or otherwise damage system resources. {see also: e-mail bomb, malicious logic, malware, Trojan horse, virus, worm}

** M **

malicious logic
Hardware, software, or firmware that is intentionally included or inserted in a system for a harmful purpose. {see also: e-mail bomb, logic bomb, malware, Trojan horse, virus, worm}

A generic term increasingly being used to describe any form of malicious software. A contraction of "malicious software". {see also: e-mail bomb, logic bomb, malicious logic, Trojan horse, virus, worm)

A measurement of digital data storage or transfer capacity, abbreviated MB. A true megabyte is equal to a kilo-kilobyte (1024*1024 bytes) or 1,048,576 bytes. This is usually confused with the advertising megabyte which is only 1,000,000 (one million) bytes.

Moore's Law
The observation made in 1965 by Gordon Moore, co-founder of Intel, that the number of transistors per square inch on integrated circuits had doubled every year since the integrated circuit was invented. Moore predicted that this trend would continue for the foreseeable future. In subsequent years, the pace slowed down a bit, but data density has doubled approximately every 18 months, and this is the current definition of Moore's Law, which Moore himself has blessed. Most experts, including Moore himself, expect Moore's Law to hold for at least another two decades.

** N **

The necessity for access to, knowledge of, or possession of specific information required to carry out official duties.

network security
Protection of networks and their services from unauthorized modification, destruction, or disclosure, and provision of assurance that the network performs its critical functions correctly and there are no harmful side-effects. Network security includes providing for data integrity.

non-public IT resources
Any IT resources that require a higher level of protection from exposure by user login or other authentication. These can also be either external (such as a study website that requires a login to access it) or internal (study websites, internal databases on servers, mapped shares, etc.) {see also: public IT resources}

** O **

That minuscule fraction of time in which you realize that your (insert function here) has been compromised.

one-time password
A password that can be used only once, usually randomly generated by special software.

outsider attack
See attack

** P **

packet monkey
Someone who intentionally inundates a Web site or network with data packets, resulting in a denial-of-service situation for users of the attacked site or network. Packet monkeys typically use tools created and made available on the Internet by hackers, but have little understanding of the harm that may be caused. Typically, packet monkey exploits are random and without any purpose other than the thrill of making an effect. {see also: ankle-biter, cracker, intruder, script kiddie}

passive attack
See attack

A data string used to verify the identity of a user.

Referred to as P2P, a type of transient Internet network that allows a group of computer users with the same networking program to connect with each other and directly access files from one another's hard drives. {see also: Health Science Center P2P policy}

Gaining unauthorized logical access to sensitive data by circumventing a system's protections.

penetration test
A system test in which evaluators attempt to circumvent the security features of the system.

personnel security
Procedures to ensure that persons who access a system have proper clearance, authorization, and need-to-know as required by the system's security policy.

The use of e-mail spam and social engineering to entice users to give up personal information (passwords, credit card information, etc.). The phishing e-mail (phish) identifies itself as being from a trusted entity (bank, credit union, service provider, credit card company, e-mail administrator, etc.)

A person who combines phone phreaking with computer hacking.

A person who hacks telephone systems, usually for the purpose of making free phone calls.

physical security
The measures used to provide physical protection of resources against deliberate and accidental threats. ("Guns, gates, and guards.")

Gaining unauthorized access to a computer system via another user's legitimate connection. This is similar to tailgating through a security checkpoint.

ping of death
A form of denial of service caused by sending oversized and malformed pings to a computer.

The copying or usage of software, music, or moview without permission from the copyright holders. There are potentially stiff penalties for software piracy. In the United States, software pirates can be punished with statutory damages of up to $100,000. If convicted of a felony charge of software piracy, offenders can get up to a five-year prison sentence plus fines of up to $250,000 for each work that is infringed.

The right of individuals to control or influence what information related to them may be collected and stored, and by whom and to whom that information may be disclosed.

An authorization or set of authorizations to perform security-relevant functions, especially in the context of a computer operating system.

public IT resources
Any non-sensitive, generally available information that can be made available without the need for individual logins or other forms of authentication. Public IT resources can be either externally available (such as the Health Science Center website and some departmental or study sites) or could be internal only (such as a departmental website with documents and information only for members of that department). Databases and other potentially sensitive or proprietary information are rarely public IT resources. {see also: non-public IT resources}

** R **

Generally, anything that can be used and/or shared while performing a function. Physical devices, such as printers, disk drives, and memory, are resources. Logical devices, such as directories, programs, files, and data, are also included. The term has recently grown to include other, more esoteric items such as time, bandwidth, and user effort.

A virus that waits until all possible backup media are infected, too, so that it is not possible to restore the system to an uninfected state. {see also: virus}

risk assessment
The process of studying the vulnerabilities, threats to, and likelihood of attacks on a computer system or network.

A collection of tools that allows a hacker to provide a back door into a system, collect information on other systems on the network, mask the fact that the system is compromised, and much more; a classic example of the use of a Trojan horse.

Hardware or software that determines the next network point to which a packet should be forwarded toward its destination; it is connected to at least two networks and decides which way to send each information packet based on its current understanding of the state of the networks it is connected to. {see also: bridge, gateway, hub, switch}

** S **

Delete sensitive data from a file, a device, or a system; or modify data so as to be able to downgrade its classification level.

script kiddie
(Also, script kiddy) A derogative term, originated by the more sophisticated crackers of computer security systems, for the more immature, but unfortunately often just as dangerous exploiter of security lapses on the Internet. The typical script kiddie uses existing and frequently well-known and easy-to-find techniques and programs or scripts to search for and exploit weaknesses in other computers on the Internet - often randomly and with little regard or perhaps even understanding of the potentially harmful consequences. Hackers view script kiddies with alarm and contempt since they do nothing to advance the "art" of hacking but sometimes unleashing the wrath of authority on the entire hacker community. While a hacker will take pride in the quality of an attack - leaving no trace of an intrusion, for example - a script kiddie may aim at quantity, seeing the number of attacks that can be mounted as a way to obtain attention and notoriety. Script kiddies are sometimes portrayed in media as bored, lonely teenagers seeking recognition from their peers. {see also: cracker, intruder, packet monkey}

security incident
A security-relevant system event in which the system's security policy is disobeyed or otherwise breached.

security intrusion
See intrusion, security

security, administrative
See administrative security

security, data
The protection of data from disclosure, alteration, destruction, or loss that either is accidental or is intentional but unauthorized. Both data confidentiality and data integrity are needed to achieve data security. {see also: confidentiality, data; integrity, data}

security, information
See information security

security, network
See network security

security, personnel
See personnel security

security, physical
See physical security

sensitive (information)
Information is sensitive if disclosure, alteration, destruction, or loss of the information would adversely affect the interests or business of its owner or user. {see also: critical}

Any computer system connected to the Health Science Center network that:
1) is a data processing device which has an assigned IP address within the University’s static IP range and is capable of either multiple simultaneous connections or any remote connections to allow use or administration of the system,
2) is a data processing device shown to be offering connectivity or services that are consistent with those that would be offered by a server (i.e. telnet, ftp, smtp, web pages, and others).

Printers and other peripheral devices with assigned static IP addresses are not servers, but desktop PCs (any OS) that host a web page or allow remote logins must be treated as servers, whether they have static IPs or not, because those services open the computer and the network up to some of the same threats as servers. Desktop computers offering shared directories and files will not be considered servers unless they are specifically designated as such by the owning department. Servers that reside on the Health Science Center network but are fully or partially owned or managed by other institutions must still meet University standards in order to remain on the network. Systems that reside on other institution’s networks but are owned by the University and used primarily for University-related functions are considered Health Science Center servers and must comply with University standards except where they conflict with established standards or functionality on the network where they reside. {see also: server, decentralized}

server, decentralized
Any server that is physically located outside of the Health Science Center Central Computing Facility or is not administered by Systems and Network Operations staff

smart card
A credit-card-sized device with embedded microelectronics circuitry for storing information about an individual.

A program and/or device that monitors data traveling over a network. Sniffers can be used both for legitimate network management functions and for stealing information off a network.

social engineering
The acquisition of sensitive information or inappropriate access privileges by an outsider, based upon the building of inappropriate trust relationships with insiders. Security experts propose that as our culture becomes more dependent on information, social engineering will remain the greatest threat to any security system. Prevention includes educating people about the value of information, training them to protect it, and increasing people's awareness of how social engineers operate.

- "Always remember: amateurs hack systems, professionals hack people."
Bruce Schneier, CTO, Counterpane Internet Security, Inc. Dec 2000

Computer instructions or data. Anything that can be stored electronically is software. The storage devices and display devices are hardware.

Verb: To indiscriminately send unsolicited, unwanted, irrelevant, or inappropriate messages, especially commercial advertising in mass quantities.

Noun: electronic "junk mail".

In sufficient volume, spam can cause denial of service. According to the SPAM Web site, the term was adopted as a result of the Monty Python skit in which a group of Vikings sang a chorus of 'SPAM, SPAM, SPAM . . .' in an increasing crescendo, drowning out other conversation. Hence, the analogy applied because unsolicited commercial e-mail was drowning out normal discourse on the Internet.

Unsolicited e-mail ("spam") on instant messaging (IM); spam + IM = spim

The process of disguising one computer user as another.

Any software that covertly gathers user information through the user's Internet connection without his or her knowledge, usually for advertising purposes; typically bundled as a hidden component of freeware or shareware programs that can be downloaded from the Internet; once installed, monitors user activity on the Internet and transmits that information in the background to someone else; can also gather information about e-mail addresses and even passwords and credit card numbers. {see also: adware, peer-to-peer, Trojan horse}

[DRAFT] Unwanted technologies that impair users' control over: material changes that affect their user experience, privacy, or system security; use of their system resources, including what programs are installed on their computers; or collection, use, and distribution of their personal information (

A network device that selects a path or circuit for sending a data to its next destination. {see also: bridge, gateway, hub, router}

** T **

The act of following an authorized user through a security checkpoint or access-controlled door. The tailgater does not have the necessary credentials but takes advantage of the authorized user not being vigilant.

A measurement of digital data storage or transfer capacity, abbreviated TB. A true terabyte is equal to a kilo-kilo-kilo-kilobyte (or mega-megabyte = 1024*1024*1024*1024 bytes) or 1,099,511,627,776 bytes. This is usually confused with the advertising terabyte which is only 1,000,000,000,000 bytes.

trap door
See back door

Trojan horse
An apparently useful and innocent program containing additional hidden code, which allows the unauthorized collection, exploitation, falsification, or destruction of data. {see also: e-mail bomb, logic bomb, malicious logic, malware, virus, worm}

** U **

uniform resource locator
Abbreviated URL, it is the standardized format for the global addresses of documents and other resources on the Internet or World Wide Web, generally in the form "protocol.organization_or_domain.domain_type". "" is the URL for the UT Health Science Center's home page on the Web; "www" is the protocol (World Wide Web), "uthscsa" is the domain, and "edu" represents an educational institution. A more detailed explanation can be found here.

** V **

A sarcastic term used to designate software and hardware products that have been announced and advertised but are not yet available.

virtual private network (VPN)
A restricted-use, logical (i.e., artificial or simulated) computer network that is constructed from the system resources of a relatively public, physical (i.e., real) network (such as the Internet), often by using encryption (located at hosts or gateways), and often by tunneling links of the virtual network across the real network. {see also: extranet, intranet}

A program or piece of code that is loaded onto a computer without the user's knowledge and runs against the user's wishes. Most viruses can also replicate themselves. {see also: e-mail bomb, logic bomb, malicious logic, malware, retro-virus, Trojan horse, worm}

virus hoax
A false warning about a computer virus. Typically, the warning arrives in an e-mail note or is distributed through a note in a company's internal network. These notes are usually forwarded using distribution lists and they will typically suggest that the recipient forward the note to other distribution lists. Though they are only hoaxes, they do serve to waste valuable network resources and personnel time and effort.

** W **

See wide area network

The slang name for pirated software (a corruption of "softwares", pronounced "wares") used by those who obtain and circulate pirated software for pleasure or profit. The term is used mostly in the US.

war dialer
A program that dials a given list or range of numbers and records those which answer with modem tones, which might be entry points to computer or telecommunications systems.

war driving
A computer cracking technique that involves driving through a neighborhood with a wireless-enabled notebook computer and mapping houses and businesses that have wireless access points.

web vs. Web
Capitalized: Either a noun or an adjective referring specifically to the World Wide Web. {see also: internet vs. Internet}

Not capitalized: Usually an adjective referring generically to technology --such as web browsers, web servers, HTTP, and HTML -- that is used in the Web or similar networks.

A hacker/cracker of wireless networks; a wireless hacker.

white hat
A hacker whose intentions are not criminal or malicious.

wide area network
A geographically dispersed telecommunications network. The term distinguishes a broader telecommunication structure from a local area network (LAN). A wide area network may be privately owned or rented, but the term usually connotes the inclusion of public (shared user) networks.

World Wide Web ("the Web", WWW, W3)
The global, hypermedia-based collection of information and services that is available on Internet servers and is accessed by browsers using Hypertext Transfer Protocol and other information retrieval mechanisms.

A program or algorithm that replicates itself over a computer network, often clogging networks and information systems as it spreads, and usually performs malicious actions, such as using up the computer's resources and possibly shutting the system down (denial of service (DoS)). {see also: denial of service (DoS), e-mail bomb, logic bomb, malicious logic, malware, Trojan horse, virus}


References: (used with much appreciation)

TECS Information Security Glossary


Internet Security Glossary

Audit My PC

Network Solutions

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