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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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  • Advanced Research Projects Agency NetworkARPANET

    A pioneering network for sharing digital resources among geographically separated computers. Its initial demonstration in 1969 led to the Internet, whose world-changing consequences unfold on a daily basis today. A seminal step in this sequence took place in 1968 when ARPA contracted BBN Technologies to build the first routers, which one year later enabled ARPANET to become operational.


  • Trusted Community RepresentativeTCR

    A trusted member of the Domain Name System’s technical and operational communities who has been selected to maintain custody of materials required for the successful operation of the root zone key signing key (KSK). By design, access to the KSK is spread across many individuals who must come together to operate the key. The TCRs play an essential role in securing the KSK and maintaining trust in the Domain Name System Security Extensions mechanism.