Skip to main content

Security, Stability, and Resiliency of the DNS – SSR Review

Sign up to learn more

Objectives of the SSR Review

ICANN has developed a plan to enhance the operational stability, reliability, resiliency, security, and global interoperability of the DNS, which will be regularly updated by ICANN to reflect emerging threats to the DNS.

Particular attention will be paid to:

  1. security, stability and resiliency matters, both physical and network, relating to the secure and stable coordination of the Internet DNS;
  2. ensuring appropriate contingency planning; and
  3. maintaining clear processes.

Timeline of Review

  • The first review shall commence one year from the effective date of the Affirmation of Commitments (i.e. 1 October 2010)
  • Further reviews to be conducted no less frequently than every three years.

One SSR Review has been completed to date, to assess the extent to which "ICANN has successfully implemented its security plan, the effectiveness of the plan to deal with actual and potential challenges and threats, and the extent to which the security plan is sufficiently robust to meet future challenges and threats to the security, stability and resiliency of the Internet DNS, consistent with ICANN's limited technical mission."

Review Call for Volunteers Review Team Announced Final Report Issued Board Action Details
SSR 1 Jun 2010 30 Sep 2010 20 Jun 2012 18 Oct 2012

30 June 2016 - original announcement

12 August 2016 - extension



​Watch a brief video by David Conrad, ICANN's CTO, as he discusses the 2nd Security, Stability and Resiliency of the DNS Review Team.

The graphic below illustrates phases and status of each review - a  indicates that all activities within a given phase have been completed.  The chart that follows the graphic provides further details of key activities and milestones within each phase – you can view these details by clicking on each of the phases in the graphic.  The table also contains links to relevant documents.

PhaseActivityDescriptionStart DateDocuments
Assemble Review TeamCall for VolunteersPublic announcement inviting volunteers to submit application30 Jun 2016
Call for Volunteers ExtensionApplication Extended for the Second Security, Stability and Resiliency (SSR-2) Review Team12 Aug 2016
Plan ReviewVariousReview team activities and detailed information available on the community wiki30 Jun 2016

PhaseActivityDescriptionStart DateDocuments
Assemble Review TeamCall for volunteersPublic announcement inviting volunteers to submit application1 Jun 2010
Appointment of review team membersAppointment of review team members30 Sep 2010
Applications receivedApplications received for SSR12 Sep 2010
SO/AC RequirementsSO/AC Requirements for Review Team Volunteers1 Jun 2010
Plan ReviewCall for Public CommentsQuestions and request for input from the community based on the SSR-RT21 Feb 2011
Terms of ReferenceDocument outlining the scope of work adopted by the review team23 Jun 2011
VariousReview team activities and detailed information available on the community wiki20 Oct 2015
Conduct ReviewRFP for independent expertsCall for Independent Experts26 Jul 2010
Draft ReportDraft report posted for public comment12 Mar 2012
Draft StatementDraft statement posted for public comment on the Review Team’s draft Recommendations #1 and #317 May 2012
Final ReportFinal report submitted to ICANN Board20 Jun 2012
Public comment on Final ReportFinal report posted for public comment21 Jun 2012
Applications receivedApplications received for independent expert on SSR6 Sep 2010
Board ActionBoard receipt of the Final ReportBoard action and resolution13 Sep 2012
Board action on review team recommendationsBoard action and resolution18 Oct 2012
Plan ImplementationPlan implementationPlan implementation19 Oct 2012
Implement ImprovementsDetails of implementation and periodic updatesInformation available on the ICANN website31 Dec 2015

Please provide your feedback here

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."