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Windows Live OneCare glossary of security and privacy terms

We know that the technical terminology used in virus alerts and descriptions can be confusing. Use this glossary whenever you come across a term you don't understand.

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A Microsoft open technology for Windows-based applications. ActiveX is not a programming language; it's a set of rules for how applications share information, often over the Internet. For example, many programs and services available on the Internet use ActiveX technology to download to your computer. See also ActiveX control.

ActiveX control
A specific implementation of ActiveX technology. For security, Microsoft developed a registration system so that your Web browser can identify and authenticate ActiveX controls before downloading them.

Advertising that is integrated into software. Adware is often combined with a host application that is provided at no charge as long as the user agrees to accept the adware.

antivirus software (AV)
A computer program designed to detect and respond to malicious software, such as viruses and worms. An antivirus program may respond by blocking access to infected files, cleaning infected files or systems, or informing the user that it has detected an infected program or file.

A deliberate attempt to compromise the security of a computer system or deprive others of the use of the system.

On local computer networks as well as the Internet, authentication is the process by which the system checks a user's logon information. The username and password are compared against an authorized list, and if the system detects a match, it grants the level of access specified in the permission list for that user. Compare with authorization.

On local computer networks as well as the Internet, authorization is the right granted to an individual to use the system and the data stored on it. Typically, a system administrator sets up authorization so that the computer or network can verify ("authenticate") user credentials (such as a code number or password) when the user logs on to the network or signs in to a Web site. Authorization is sometimes called "access privileges" or "permission." Compare with authentication.

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back door
A hardware or software-based hidden entrance to a computer system that can be used to bypass the system's security policies.

Describes communications systems in which the medium of transmission (such as wire or fiber-optic cable) can carry multiple messages at a time. Each message is modulated on its own carrier frequency to keep it distinct from other message packets. Broadband Internet connections are the fastest currently available to home users. A broadband connection allows the user to download large data files more quickly, or to play video and music files over the Internet or a local network.

A region of computer memory in which data is temporarily stored before it is transferred between two locations or devices. For example, video or music files, which contain large amounts of data, are often downloaded into a buffer before your media program plays the file. This avoids gaps or interruptions in the flow of the video or music file when it plays.

buffer overrun
A condition that results from adding more information to a buffer than it was designed to hold. An attacker may exploit this vulnerability to take over a system.

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Cable modem
A modem that sends and receives data through a coaxial cable television network, instead of through telephone lines as a conventional modem does. Cable modems, which generally transmit data faster than current conventional phone modems, are a type of broadband connection.

Children's Online Privacy Protection Act (COPPA)
A U.S. law that took effect on April 21, 2000, and requires parental consent for certain Web sites to knowingly collect personally identifiable information on children under the age of 13. Learn more about COPPA.

Content Advisor
A tool in Microsoft Internet Explorer that lets you control which sites users on your computer can visit. This is particularly helpful for parents who want to control the content their children view on the Web.

A small data file that is stored on a user's local computer for record-keeping purposes and which contains information about the user that is pertinent to a Web site, such as user preferences.

critical update
A broadly released fix for a specific problem addressing a critical, non-security-related bug.

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denial of service attack (DoS)
A malicious attempt to prevent legitimate users from accessing a resource (usually an Internet service) by exploiting a weakness or design limitation in an information system. The command program for DoS attacks may be distributed through a virus or other means. A DoS attack may flood network connections with fake communications (like phony e-mails and sign in attempts), fill disk storage, disable network ports, or remove power.

digital certificate
1. An assurance that software downloaded from the Internet comes from a reputable source. A digital certificate provides information about the software, such as the identity of the author and the date on which the software was registered. 2. An online identity card or "driver's license" that functions as a user's electronic credentials. Digital certificates may be used both on the Internet and on intranets such as corporate or home networks. Digital certificates ensure the legitimate online transfer of confidential information, money, or other sensitive materials by means of encryption technology. Compare with digital signature.

digital signature
Data that binds a sender's identity to the information being sent. A digital signature may be bundled with any message, file, or other digitally encoded information, or transmitted separately. Digital signatures are used in public key environments and provide nonrepudiation and integrity services. Compare with digital certificate.

Acronym for Digital Subscriber Line, a recently developed (late 1990s) digital communications technology that can provide high-speed transmissions over standard copper telephone wiring. Currently, ADSL (Asymmetric DSL) is the form of DSL most often provided by telephone companies. DSL is a type of broadband Internet connection.

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e-mail bomb
A denial of service attack in which an excessive amount of e-mail data is sent to an e-mail address in an attempt to disrupt the e-mail service, or to prevent the recipient from receiving legitimate messages.

The process of encoding (scrambling) electronic information in such a way that it is unreadable to all but those individuals possessing the key to the code. Encrypted information is known as cipher text.

encryption key
A sequence of data (or key) that is used to encrypt other data. The same encryption key must be used to decrypt or unlock the data. See encryption.

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A security solution which segregates one portion of a network from another portion, allowing only authorized network traffic to pass through according to traffic filtering rules.

full file replacement
A technology used in hotfixes that replaces the currently installed files with new files. Compare patching.

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globally unique identifier (GUID)
A 16-byte value generated from the unique identifier on a device, the current date and time, and a sequence number. A GUID is used to identify a particular device, component, user, or session.

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high priority update
A classification used on the Windows Update Web site and by the Windows Update Service to recommend Microsoft software updates and drivers that help protect against the latest publicly known security threats and reliability issues. All software updates and drivers that can be installed by turning on Automatic Updates on your computer are classified as high priority. These can also be installed by visiting the Windows Update Web site.

A single cumulative package composed of one or more files used to address a problem in a product. Hotfixes address a specific customer situation and may not be distributed outside the customer organization. The terms QFE, patch, and update have been used in the past as synonyms for hotfix.

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Internet Content Rating Association (ICRA)
An international nonprofit group that has developed a content advisory service for the Internet. ICRA's aim is to protect children from potentially harmful material on the Internet.

Acronym for Internet Relay Chat, a service that enables Internet users to chat online in real time. An IRC server opens and maintains an IRC channel which transmits text typed by each user who has joined the channel to all other users who have joined the channel. Invented in 1988, IRC has largely been replaced as a chat tool by instant messaging services such as MSN® Messenger. However, authors of malicious software sometimes use IRC services to infect machines or execute DoS attacks.

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A programming language developed by Sun Microsystems, Inc. Java was designed to be secure and platform-neutral (meaning that it can run on any type of computer), which makes it a useful language for programming Web applications because users access the Web from many types of computers. Java is popular for programming small applications, or applets, for the World Wide Web. See also Java applet.

Java applet
A small Java application that is run by a Web browser. Java applets are frequently used to add multimedia effects and interactivity to Web pages, such as background music, real-time video displays, animations, calculators, and interactive games. Some applets are activated automatically when you view a Web page, while others may require you to take some action, such as clicking an icon in the Web page. See Java.

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mail relaying
A practice in which an attacker sends e-mail messages from another system's e-mail server in order to use its resources and/or make it appear that the messages originated from the other system.

malicious code
Software that fulfills the deliberately harmful intent of an attacker when run. For example, viruses, worms, and Trojan horses are malicious code.

Jargon for "malicious software"; that is, software written by hackers to infect computers, steal personal information, destroy files, launch denial of service attacks, and so on. See malicious code.

Microsoft security bulletin
A document that describes a specific security issue in Microsoft software and directs the reader to a downloadable file that resolves the issue.

Microsoft virus alert
An announcement from Microsoft that describes a specific virus, the impact of potential attacks on Microsoft software, and suggestions for preventing or recovering from such attacks.

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Office Update
A Microsoft Web site maintained by the Microsoft Office product group for the purpose of providing critical updates, add-ins, converters, and viewers that increase the performance and stability of currently released Office programs.

opt in
To explicitly consent to participate. Typically used in marketing programs and offerings, whereby an action (such as the use of personal information beyond the original, primary purpose for which it was collected) is not undertaken unless an individual explicitly consents.

opt out
To explicitly decline to participate. Typically used in marketing programs and offerings, whereby an action (such as the use of personal information beyond the original, primary purpose for which it was collected) is undertaken unless an individual explicitly declines.

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A string of characters entered by a user to verify his or her identity to a network or to a local computer. See also strong password and weak password.

See security update.

A method of updating a file that replaces only the parts being changed, rather than the entire file. Compare full file replacement.

Authorization to perform operations associated with a specific shared resource, such as a file, directory, or printer. Permissions must be granted by the system administrator to individual user accounts or administrative groups.

personal data
See personally identifiable information.

personally identifiable information (PII)
Any information relating to an identified or identifiable individual. Such information may include name, country, street address, e-mail address, credit card number, Social Security number, government ID number, IP address, or any unique identifier that is associated with PII in another system. Also known as personal information or personal data.

A malicious user or Web site that deceives people into revealing personal information, such as account passwords and credit card numbers. A phisher typically uses deceptive e-mail messages or online advertisements as bait to lure unsuspecting users to fraudulent Web sites, where the users are then tricked into providing personal information.

See personally identifiable information.

pop-up blocker
Software or application that disables any pop-up (or pop-over or pop-under) advertisement window that you would normally get while browsing the Web. Many current Web browsers, including Internet Explorer, come with automatic pop-up blocking features. Some pop-up blockers may try to close all pop-up windows, while others offer the user the option to decide which pop-ups to allow. Because some legitimate Web applications use pop-up windows, there will be times when you'll need to disable your pop-blocker, or configure it to always allow pop-ups for the specific Web page or site.

The control customers have over the collection, use, and distribution of their personal information.

privacy compromise
A scenario in which an unauthorized individual is able to gain access to personal or confidential information about another user.

privacy policy
An organization's requirements for complying with privacy regulations and directives. The policy is expressed in a privacy statement.

privacy statement
A document describing a company's position on privacy, detailing what information its Web site collects, with whom the data is shared, and how users can control the use of their personal data.

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A form of Internet extortion in which malicious software encrypts the files on a computer so that the user cannot access them. The infection then leaves a "ransom note" message file instructing the user to send payment to the hacker in order to get the digital keys to unlock the encrypted files.

remote attack
An attack that targets a computer other than the one that the attacker is interactively logged on to. For example, an attacker can log on to a workstation and attack a server on the same network or on an entirely different one.

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security update
A broadly released fix for a product-specific, security-related vulnerability. Security vulnerabilities are rated based on their severity, which is indicated in the Microsoft security bulletin as critical, important, moderate, or low.

security vulnerability
A vulnerability in software that is addressed by a Microsoft security update and security bulletin or a service pack.

service pack
A tested, cumulative set of all the hotfixes, security updates, critical updates, and updates created to fix defects in a piece of software found internally since the release of the software. Service packs may also contain a limited number of customer-requested design changes or features. For example, Windows® XP Service Pack 2 (SP2) includes important security updates for the Windows XP operating system.

service release
See service pack.

signed program
A program with a digital certificate.

software update
Any update, update rollup, service pack, feature pack, critical update, security update, or hotfix used to improve or fix software released by Microsoft.

Unsolicited commercial e-mail. Also known as junk e-mail.

To make a transmission appear to come from a user other than the user who performed the action.

strong password
A password that provides an effective defense against unauthorized access to a resource. A strong password is at least six characters long, does not contain all or part of the user's account name, and contains at least three of the four following categories of characters: uppercase letters, lowercase letters, base 10 digits, and symbols found on the keyboard, such as !, @, and #.

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Trojan horse
A program that appears to be useful or harmless but that contains hidden code designed to exploit or damage the system on which it is run. Trojan horse programs are most commonly delivered to users through e-mail messages that misrepresent the program's purpose and function. Also called Trojan code.

An organization offering an online privacy seal program that certifies eligible Web sites and holds Web sites to a baseline privacy standard. This key privacy watchdog organization plays an important enforcement role in the dispute and resolution of privacy issues.

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update (noun)
A broadly released fix for a specific problem addressing a noncritical, non-security-related bug. Compare with service pack, software update.

update (verb)
To make a system or data file more current.

upgrade (noun)
A software package that replaces an installed version with a newer version of the same software. The upgrade process typically leaves existing customer data and preferences intact while replacing the existing software with the newer version.

upgrade (verb)
To change to a newer, usually more powerful or sophisticated version.

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Code written with the express intention of replicating itself. A virus attempts to spread from computer to computer by attaching itself to a host program. It may damage hardware, software, or data. Compare with worm.

virus definition
Also known as a virus signature. A recognized pattern of unique computer code contained in a virus. Antivirus programs search for these known patterns to identify infected programs and files. In the same way that new vaccines must be developed to combat different strains of flu, antivirus software must be updated constantly with new virus definitions. Windows Live OneCare Antivirus updates your computer with the latest definitions each time you connect to the Internet.

Any weakness, administrative process or act, or physical exposure that makes a computer susceptible to exploit by a threat.

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weak password
A password that does not provide an effective defense against unauthorized access to a resource. A weak password might be less than six characters long, contain all or part of a user's account name, or contain less than three of the four following categories of characters: uppercase letters, lowercase letters, base 10 digits, and symbols found on the keyboard, such as !, @, and #.

Windows Live™ ID (formerly Microsoft® Passport Network )
Windows Live ID is a Web-based service designed to make signing in to Web sites fast and easy. It enables participating Web sites to authenticate a user with a single set of sign-in credentials (e-mail address and password), thereby alleviating the need for users to remember numerous passwords and user names.

Windows Update
1. A Microsoft Web site maintained by the Windows product group for the purpose of providing updates for core Windows components. 2. An application in Windows that enables a user to download files from the Internet that are necessary to keep a computer up to date.

Self-propagating malicious code that can automatically distribute itself from one computer to another through network connections. A worm can take harmful action, such as consuming network or local system resources, possibly causing a denial of service attack. Compare virus.

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