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ICANN Approves Name Collision Occurrence Management Framework | Special IP Address (127.0.53.53) Alerts System Administrators of Potential Issue

1 August 2014

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ICANN today announced the approval of the Name Collision Occurrence Management Framework [PDF, 634 KB] by the ICANN Board New gTLD Program Committee (NGPC). The framework implementation requirements were developed with input from many sources including the ICANN community, a report published by JAS Global Advisors LLC, and advice from the Security and Stability Advisory Committee (SSAC).

The framework is designed to mitigate the impact of name collisions in the domain name system (DNS), which typically occur when fully qualified domain names conflict with similar domain names used in private networks. When this occurs, users can be taken to an unintended Web page or encounter an error message.

To address this issue, the framework calls for registry operators to use a technique called "controlled interruption" to alert system administrators that there may be an issue in their network. Specifically, an IPv4 address – 127.0.53.53 – will appear in system logs, enabling a quick diagnosis and remediation.

"We now have a well-defined methodology for mitigating name collisions for delegated top-level domain names and a path forward for registries to unblock certain second-level domains in their list," said Akram Atallah, president of ICANN's Global Domains Division. "These operational processes, which were developed in conjunction with the multistakeholder community, will help to ensure the security of the domain name system."

Atallah went on to note that ICANN will provide information to and work with the Generic Names Supporting Organization (GNSO) to consider whether policy work on developing a long-term plan to manage gTLD name collisions issues should be undertaken.

ICANN will be holding webinars to discuss details of the Name Collision Occurrence Management Framework and answer questions on 12 August 2014 – Session 1 will take place at 01:00-02:30 UTC and Session 2 will be from 15:00-16:30 UTC.

Overview: Name Collision Occurrence Management Framework Implementation

ICANN registry operators are obligated to comply with requirements in the Name Collision Occurrence Management Framework, which include:

  • Acting on name collision reports from ICANN within two hours of receipt of the report during the first two years of the life of the top-level domain (TLD), measured from the time of delegation of the TLD;
  • Implementing continuous controlled interruption for a 90-day period.

ICANN obligations include:

  • Monitoring the registry's implementation of the controlled interruption to ensure compliance with contractual requirements;
  • Coordinating an emergency response for name collision reports only where there is a reasonable belief that the name collision presents a clear and present danger to human life; and
  • Working within the Internet Engineering Task Force (IETF) and with other relevant technical communities to identify a mechanism for IPv6 IP addresses that provides similar functionality to that being used in IPv4 (the loopback IP address 127.0.53.53).

The Name Collision Occurrence Management Framework also calls for the delegation of .CORP, .HOME, and .MAIL to be deferred indefinitely. ICANN will collaborate with the technical and security communities to determine the best way to handle these strings in the long term.

For more information on name collisions please visit https://www.icann.org/namecollision.

About ICANN

ICANN's mission is to ensure a stable, secure and unified global Internet. To reach another person on the Internet you have to type an address into your computer - a name or a number. That address has to be unique so computers know where to find each other. ICANN coordinates these unique identifiers across the world. Without that coordination we wouldn't have one global Internet. ICANN was formed in 1998. It is a not-for-profit public-benefit corporation with participants from all over the world dedicated to keeping the Internet secure, stable and interoperable. It promotes competition and develops policy on the Internet's unique identifiers. ICANN doesn't control content on the Internet. It cannot stop spam and it doesn't deal with access to the Internet. But through its coordination role of the Internet's naming system, it does have an important impact on the expansion and evolution of the Internet. For more information please visit: www.icann.org.

[UPDATE: The date of the Session 1 webinar on the Name Collision Occurrence Management Framework has changed. It will now take place from 01:00-02:30 UTC on 12 August 2014.]