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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.


2 February 2016 – Emergency Registry Operator Transition Simulation Successful

ICANN has completed a test of the Emergency Back-End Registry Operator (EBERO) program. The test resulted in the successful transition of operations from an existing registry to Nominet, an EBERO service provider based in the U.K.

The procedures that have been implemented as part of the EBERO Program to protect against a potential registry service interruption worked as planned. Lessons learned during this exercise will help the team responsible for executing the EBERO Program refine its processes.

ICANN thanks all companies that participated in this exercise. The effort that went into simulating an EBERO event will support ICANN's efforts to ensure the security, stability and resiliency of the Internet and the Domain Name System.

ICANN's EBERO providers must meet stringent technical requirements and have demonstrated years of experience in operating Domain Name Services, Registration Data Directory Services and Extensible Provisioning Protocol Services. In addition to Nominet, ICANN has contracted with the China Internet Network Information Center and Core Association to provide EBERO services.


The establishment of Emergency Back-End Registry Operators, or EBEROs, are an important innovation of the New gTLD Program. The EBERO program mitigates risks to the stability and security of the Domain Name System in the event of New gTLD operator failure.

Emergency back-end registry operators are temporarily activated if a TLD registry operator is at risk of failing to sustain any of the five critical registry functions. These functions are:

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

EBEROs are limited in the services they can provide. For example, EBEROs will not provide any additional services that a TLD 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.

More Information

EBERO Provider Signed Agreements

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."