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Mitigating DNS Namespace Collisions

26 February 2014

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In line with our ongoing commitment to preserve the security, stability and resiliency of the Internet’s Identifier systems, ICANN today published a report on collisions in the DNS namespace as they relate to the New TLD program.  We would like to thank JAS Global Advisors LLC for its role in performing the studies and in writing the “Mitigating the Risk of DNS Namespace Collisions” report.

It should be noted that the report is technical in nature and requires some understanding of namespace collisions to be fully appreciated. With that in mind, I recommend that readers become familiar with the issue by reading the guide and FAQ at http://www.icann.org/en/help/name-collision.

The full report can be found at: https://www.icann.org/en/about/staff/security/ssr/name-collision-mitigation-26feb14-en.pdf [PDF, 322 KB]

Over the course of the study, JAS found “no evidence to suggest that the security and stability of the global Internet DNS itself is at risk”. The JAS report further confirms the results of the “DNS Stability String Review” performed on each string during Initial Evaluation pursuant to Section of the Applicant Guidebook.

The report includes a series of recommendations for mitigating risks associated with the new gTLD program, specifically those related to Domain Name Collisions. Among the recommendations:

  • The Top Level Domains .corp, .home and .mail should be permanently reserved.
  • ICANN should require new TLD registries to publish a controlled interruption zone immediately upon delegation in the root zone.
    • Details how a controlled interruption mechanism would work are covered in the report.
    • After the 120-day period, there shall be no further collision-related restrictions on the registry.
  • ICANN should have emergency response processes in place on 24x7x365 basis that include the abilities to analyze and act upon reported problems that present “clear and present danger to human life”.
  • ICANN and others in the community should continue to collect and analyze data relating to the root servers and to the controlled interruption.

In studying collision data for the report, JAS uncovered a vulnerability that is “not directly related to ICANN’s New gTLD Program nor to new TLDs in general but has the potential to impact end-systems”. JAS and ICANN are working with affected (vendor) parties pursuant to ICANN’s Coordinated Vulnerability Disclosure Process.

https://www.icann.org/en/about/staff/security/vulnerability-disclosure-11mar13-en.pdf [PDF, 470 KB]

Due to the need to keep certain aspects of the discovered vulnerability confidential, as per the vulnerability disclosure process, JAS is reluctant to disclose experimental methods or data at this time, but has in this report provided a summary of recommendations based on its study of the occurrence and severity of namespace collisions in the global Internet DNS.

ICANN is actively seeking community input on the recommendations through ICANN’s public comment processes.

I would encourage anyone with interest to read the report and to make comments.



John Crain

John Crain

SVP & Chief Technology Officer