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Emergency Back-end Registry Operator

Note: The English language version of all content and documents in this section is the official version. Translations in other languages are for informational purposes only.


The establishment of Emergency Back-end Registry Operators, or EBEROs, are an important innovation of the New gTLD Program. An EBERO provider is temporarily activated if a generic Top-Level Domain (gTLD) operator is at risk of failing to sustain any of the five critical registry functions. Ensuring the availability of these functions protects registrants, also known as domain name holders, and provides an additional layer of protection to the Domain Name System (DNS), and industry ecosystem. These five critical registry functions are:

  1. DNS resolution for registered domain names
  2. Operation of Shared Registration System
  3. Operation of Registration Data Directory Services
  4. Registry data escrow deposits
  5. Maintenance of a properly signed zone in accordance with DNSSEC requirements

EBERO providers are limited in the services they can provide. For example, EBERO providers will not provide any additional services that a gTLD operator may have offered its customers, such as web hosting or network analytics.

The currently contracted organizations meet stringent technical requirements and have demonstrated years of experience in operating domain name services, registration data directory services and extensible provisioning protocol services. They are:

ICANN is responsible for declaring an event requiring EBERO emergency services and coordinating all emergency response activities. EBERO does not apply to some Legacy gTLDs.

More Information

Current EBERO Provider Signed Agreements

Additional Agreement Information


Previous EBERO Provider Signed Agreements

  • CNNIC (Aug 2013 – Aug 2019) [PDF, 1.04 MB]
  • CORE Association (Aug 2013 – Aug 2019) [PDF, 1.02 MB]
  • Nominet (Jan 2014 – Aug 2019) [PDF, 905 KB]
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."