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Name Collision Resources & Information

Overview: What is a Name Collision?
Resources for IT Professionals
127.0.53.53
Resources for Registry Operators
ICANN's Role in Addressing Name Collision
Archive


Overview: What is a Name Collision?

A name collision occurs when an attempt to resolve a name used in a private name space (e.g. under a non-delegated Top-Level Domain, or a short, unqualified name) results in a query to the public Domain Name System (DNS). When the administrative boundaries of private and public namespaces overlap, name resolution may yield unintended or harmful results.

Name collisions are not new. The introduction of any new domain name into the DNS, whether a generic TLD, country code TLD or second-level domain name, creates the potential for name collision. However, queries for un-delegated TLDs at the root level of the DNS have received renewed attention because certain applied-for new TLD strings could be identical to name labels used in private networks. A secure, stable and resilient Internet is ICANN's number one priority. Therefore, we've made a commitment to the Internet community to launch a substantial effort to mitigate and manage name collision occurrence.

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Resources for IT Professionals

The following materials have been created to help IT Professionals understand and address the root cause of name collision. The video below provides a quick overview of the situation and resources available.

 

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127.0.53.53

127.0.53.53 is a special IPv4 address that will appear in system logs alerting system administrators that there is potential name collision issue, enabling a quick diagnosis and remediation. The "53" is used as a mnemonic to indicate a DNS-related problem owing to the use of network port 53 for the DNS service.

System administrators that encounter a system error due to name collision are encouraged to take the following steps:

  1. Report the problem to ICANN »
    Instances where there is a reasonable belief of demonstrable, severe harm as a consequence of a name collision should be reported.
  2. Read the Guide to Name Collision Identification and Mitigation for IT Professionals (version 1.1) [PDF, 476 KB] and implement the measures outlined therein.
  3. Spread the word about the potential for name collision occurrence and mitigation in your professional circle.

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Resources for Registry Operators

The Name Collision Occurrence Management Framework was created to mitigate the impact of name collisions in the domain name system (DNS). It calls for Registry Operators to implement a controlled interruption for a period of 90 days to alert system administrators that there may be an issue in their network, and to have an emergency response capability in place. Operators will find the materials below to be informative resources on this and other Name Collision related issues.

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ICANN's Role in Addressing Name Collision

It is unlikely that domain name collisions will affect significant numbers of corporate network operators or Internet users. However, ICANN considers it essential that it does everything possible to minimize potential impact and to offer clear advice on dealing with the issue. Below is an overview of the steps ICANN has taken, in partnership with the Internet community, to address name collision. A detailed list of information and publications regarding name collision dating back to 2010 is available in the Archive section of this webpage.

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Archive

Document: Final "Phase One Report on Mitigating the Risk of DNS Namespace Collisions" [PDF, 392 KB]
Publication Date: 10 June 2014
ICANN publishes the final "Mitigating the Risk of DNS Namespace Collisions Phase One" report by JAS Global Advisors ("JAS").

Document: SSAC Comments on draft version of JAS' Phase One Report [PDF, 306 KB]
Publication Date: 6 June 2014
ICANN's Security and Stability Advisory Committee issues comment on the draft version of the JAS Phase One Report on Mitigating the Risk of DNS Namespace Collisions.

Document: Draft "Phase One Report on Mitigating the Risk of DNS Namespace Collisions" [PDF, 322 KB]
Publication Date: 26 February 2014
ICANN published a proposed means of mitigating name collision crafted by JAS Global Advisors. Public comment was solicited on this proposal.

Announcement: Independent Report Maps Possible Way Forward in Mitigating Domain Name Collisions
Publication Date: 26 February 2014
An independent report commissioned by ICANN, Mitigating the Risk of DNS Namespace Collisions, has offered a set of concrete recommendations on how to mitigate potential risks of domain name collisions.

News Release: ICANN Issues Advice to IT Professionals on Name Collision Identification and Mitigation
Publication Date: 6 December 2013
A general explanation of the report (above) for IT Professionals and why it's necessary.

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Blog Post: Managing Name Collision Occurrences
Publication Date: 6 December 2013
ICANN's VP, Security and ICT Coordination, Dave Piscitello, provides further information on the "Name Collision Identification and Mitigation for IT Professionals" report and recommends a solution for treating the problem at its root.

Document: Guide to Name Collision Identification and Mitigation for IT Professionals (version 1.0) [PDF, 228 KB]
Publication Date: 5 December 2013
Intended for IT Professionals who may find their networks affected by name collision, this report [version 1] provides extensive information on the causes and potential effects, and offers guidance on how and when to launch mitigation efforts.

Announcement: New gTLD Collision Occurrence Management Plan Frequently Asked Questions
Publication Date: 3 December 2013
ICANN provides the most sought-after information regarding name collision occurrence.

Meeting Content: Name Collision Update at ICANN 48 in Buenos Aires
Publication Date: 19 November 2013
A session that allow chart the way forward on Name Collision.

Meeting Content: Security and Stability Update at ICANN 48 in Buenos Aires
Publication Date: 18 November 2013
An open community session wherein the Security Team presented and opened discussion on the latest developments regarding Security, Stability, and Resiliency in regard to new gTLDs.

Announcement: ICANN Selects Lead for Development of Name Collision
Publication Date: 11 November 2013
ICANN signed an agreement with JAS Global Advisors LLC to lead the development of the Name Collision Occurrence Management Framework, in cooperation with the community.

Document: AC062 SSAC Advisory Concerning the Mitigation of Name Collision Risk [PDF, 382 KB]
Publication Date: 7 November 2013
An Advisory to the ICANN Board from the Security and Stability Advisory Committee (SSAC) concerning ICANN's proposal to mitigate name collision risks.

Questions & Answers: New gTLD Applicant Update Webinar – 23 October 2013 [PDF, 223 KB]
Publication Date: 23 October 2013
Answers to questions about Name Collision raised by New gTLD Webinar participants.

Blog Post: How the 2013.10.07 NGPC Resolution on Name Collision Affects the New gTLD Program Contracting Process
Publication Date: 20 October 2013
After several months of work including input from numerous members of the ICANN community, the New gTLD Program Committee (NGPC) has taken action on two key issues affecting applicants of the program – GAC Category 2 Advice and Name Collision.

Announcement: NGPC Resolution on Name Collision Requires Registry Agreement Update
Publication Date: 16 October 2013
The adoption of the 2013.10.07 resolution by the New gTLD Program Committee of the ICANN Board cleared the way for new gTLDs to move forward to Delegation, while addressing concerns about Name Collision raised by the community. In order to comply with the NGPC's Resolution, ICANN made a "Required Change" to Specification 6 of the Registry Agreement for new gTLDs.

Blog Post: Moving Forward with Delegation of Top-Level Domains
Publication Date: 9 October 2013
ICANN's New gTLD Program Committee (NGPC) has approved resolutions allowing us to move forward in expanding the Internet's name space while mitigating possible issues in the expansion.

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Document: New gTLD Collision Occurrence Management [PDF, 841 KB]
Publication Date: 7 October 2013
ICANN staff created a proposal to manage collision occurrences between new gTLDs and existing private uses of the same strings. This proposal was approved by the NGPC.

Statement: ALAC Welcomes Proposal to Mitigate Name Collision
Publication Date: 27 August 2013
The ALAC welcomes the completion and publication of the "Name Collisions in the DNS" study report by Interisle Consulting Group and the subsequent response by ICANN in "New gTLD Collision Risk Management Proposal.

Board Resolutions: New gTLD Collision Occurrence Management Program
Publication Date: 7 August 2013
The New gTLD Program Committee (NGPC) of the ICANN Board approved resolutions directing ICANN staff to manage the occurrence of collisions between new gTLDs and existing private uses of the same strings, and enact the proposed name collision outreach campaign.

Public Comment: Proposal to Mitigate Name Collision Risks
Publication Date: 5 August 2013
Purpose: To solicit community comment on proposed efforts to mitigate potential impact resulting from name collisions as New gTLDs are delegated into the root zone.

Document: New gTLD Collision Risk Mitigation [PDF, 166 KB]
Publication Date: 5 August 2013
Proposal to manage the collision occurrences between new gTLDs and existing private uses of the same strings.

Announcement: Addressing the Consequences of Name Collisions
Publication Date: 5 August 2013
As directed by the ICANN Board of Directors on 18 May 2013, ICANN commissioned and released the results of a study that considers the likelihood and impact of name space collisions between applied-for newgTLD strings and non-delegated TLDs.

Study: Name Collision in the DNS [PDF, 3.34 MB]
Publication Date: 2 August 2013
A study of the likelihood and potential consequences of collision between new public gTLD labels and existing private uses of the same strings. Performed by third party researcher, Interisle.

Meeting Content: Security, Stability & Resiliency Update at ICANN 47 Durban
Publication Date: 17 July 2013
A community session intended to discuss security and stability topics and shed light on the study on name collision.

Board Resolution: SSAC Advisory on Internal Name Certificates
Publication Date: 18 May 2013
The ICANN Board of Directors directs staff, in consultation with the ICANN Security and Stability Advisory Committee (SSAC), to commission a study on the use of TLDs that are not currently delegated at the root level of the public DNS in enterprises, which considers the potential security impacts of applied-for new-gTLD strings in relation to this usage.

Report: SAC 045 – Invalid Top Level Domain Queries at the Root Level [PDF, 507 KB]
Publication Date: 15 November 2010
The ICANN Security and Stability Advisory Committee (SSAC) calls attention to the potential problems that may arise name collision in this report, which was published for community and Board review.

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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""icann.org"" is not an IDN."