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Demystifying the Root Zone

Root zone demystifying 750x425 09jul14 en

Click infographic for larger version

In our interactions with a wider community of Internet users and evolving set of participants and decision makers, ICANN's Global Stakeholder Engagement team often meets with people who ask how the Internet and the Domain Name System works. To help address this need for a basic overview, a cross-organizational team along with our creative partners at XPLANE, developed an infographic to explain the role of the root zone, how it is managed, maintained and secured. This infographic was previewed with small groups of stakeholders during the ICANN 50 meeting in London, and now we are making this first version more widely available for information and awareness.

I know there must be a balance in presenting technical concepts in a readable, cohesive manner to the satisfaction of a technical audience and ICANN's expert community while delivering information that is accessible and educational to a more general audience. We think we have achieved that.

If you have questions or concerns about the infographic, please contact me directly ( I would also like to thank those who provided input and feedback on earlier versions of the infographic. This should be a useful addition to the materials available about the root zone and its role in the Domain Name System. Our next step is to make language translations of this infographic.

Patrick Jones is Senior Director, Global Stakeholder Engagement at ICANN


    Domain Name System
    Internationalized Domain Name ,IDN,"IDNs are domain names that include characters used in the local representation of languages that are not written with the twenty-six letters of the basic Latin alphabet ""a-z"". An IDN can contain Latin letters with diacritical marks, as required by many European languages, or may consist of characters from non-Latin scripts such as Arabic or Chinese. Many languages also use other types of digits than the European ""0-9"". The basic Latin alphabet together with the European-Arabic digits are, for the purpose of domain names, termed ""ASCII characters"" (ASCII = American Standard Code for Information Interchange). These are also included in the broader range of ""Unicode characters"" that provides the basis for IDNs. The ""hostname rule"" requires that all domain names of the type under consideration here are stored in the DNS using only the ASCII characters listed above, with the one further addition of the hyphen ""-"". The Unicode form of an IDN therefore requires special encoding before it is entered into the DNS. The following terminology is used when distinguishing between these forms: A domain name consists of a series of ""labels"" (separated by ""dots""). The ASCII form of an IDN label is termed an ""A-label"". All operations defined in the DNS protocol use A-labels exclusively. The Unicode form, which a user expects to be displayed, is termed a ""U-label"". The difference may be illustrated with the Hindi word for ""test"" — परीका — appearing here as a U-label would (in the Devanagari script). A special form of ""ASCII compatible encoding"" (abbreviated ACE) is applied to this to produce the corresponding A-label: xn--11b5bs1di. A domain name that only includes ASCII letters, digits, and hyphens is termed an ""LDH label"". Although the definitions of A-labels and LDH-labels overlap, a name consisting exclusively of LDH labels, such as"""" is not an IDN."