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Centralized Zone Data Service (CZDS)

Please note that the English language version of all translated content and documents are the official versions and that translations in other languages are for informational purposes only.

The Centralized Zone Data Service provides a centralized point for interested parties to request access to Zone Files provided by participating Top Level Domain Registries. The service is the solution for scaling zone data transfer as hundreds of new gTLDs are added to the Internet.

Every new gTLD Registry is required to provide zone data to approved requesters (e.g. law enforcement agents, IP attorneys, researchers) upon technical delegation of its gTLD.

New Registries will be provided with instructions for utilizing the Centralized Zone Data Service once a gTLD Registry Agreement has been executed.

CZDS for End Users

  • The Centralized Zone Data Service has been created to simplify the process for end-users to request zone data and enter into individual and standardized agreements with the registries that provide TLD Zone Files.
  • Help for CZDS
  • Go to the CZDS end-user portal

CZDS for Registries

  • CZDS simplifies the process of entering into zone data contracts. Rather than creating and executing a contract for every request, Registries can simply approve or deny requests with one click.
  • Registries can save additional time by appointing ICANN to handle zone data file transfer (AXFR), formatting, and distribution to approved end-users instead of using internal resources.

Using the Centralized Zone Data Service

Terms and Conditions


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."