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ICANN Acronyms and Terms

ICANN has hundreds of acronyms and terms, which can be confusing. We created this multilingual tool to help explain what these terms mean and facilitate your work within the ICANN community. Search for terms by name or acronym using the search bar, or search by letter. All acronyms and terms are available in Arabic, Chinese, French, Russian, and Spanish.

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  • malware

    Any software that, when installed, performs unwanted or malicious activity, often for the benefit of a third party. Adware, spyware, and viruses are some well-known forms of malware.

  • malware hosting

    A scheme in which cyberattackers conceal malicious software files (malware) on a website to infect computers that visit the site. Often, the attackers place these files on legitimate websites without the site owner’s knowledge. When victims click a link that leads to the malicious software files, their computers are infected. In some cases, attackers distribute links to the malicious files through spam, adware, or mobile in-app advertising. In other cases, they rely on the site’s popularity to attract victims.

  • man-in-the-middle attackMITM attack

    Any attack in which the attacker secretly interposes software or a computer system to intercept, capture, alter, or replay messages between two parties. Attackers use MITM attacks to capture information that one party transmits to another. Installing malware to record a computer user’s keystrokes is one form of MITM attack. In more elaborate schemes, an attacker impersonates one or both parties in an email exchange. During the email exchange, the attacker aims to dupe one of the parties into divulging sensitive information or authorizing a financial transaction.

  • Material Subcontracting ArrangementMSA

    Any subcontracting arrangement that relates to one or more of the critical functions identified in the Registry Agreement for generic top-level domains. A subcontractor that participates in an MSA is often referred to as a back-end service provider or a registry service provider.

  • Maximal Starting RepertoireMSR

    A template that provides the basis for updates to the Root Zone Label Generation Rules (RZ-LGR). The MSR contains:

    A Generation Panel (GP) uses the MSR as its starting point to create RZ-LGR for a particular script or writing system.

    The MSR is updated from time to time based on feedback from the community and to accommodate relevant updates to the Unicode Standard. Each new version of the MSR is given a version number in the form MSR-# (e.g., MSR-1, MSR-2, MSR-3).

  • media type

    An identifier (formerly known as a MIME type) that some protocols use to indicate the nature and format of files sent over the Internet. A file’s media type appears in the header of a file transmission and indicates the file’s type and subtype. Common type/subtype values include:

  • Messaging, Malware and Mobile Anti-Abuse Working GroupM3AAWG

    An association of global stakeholders that work cooperatively to target abusive messaging, malware, and other new forms of online abuse. The M3AAWG publishes best practices and provides training and educational materials on fighting abuse. Its membership includes Internet service providers, telecom companies, email service providers, and social networking companies.

    ICANN is a participant in the M3AAWG.

  • Multipurpose Internet Mail Extensions typeMIME type