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Root Zone Management System Parallel Testing

Status of Parallel Testing

5 July 2016: The parallel testing period successfully completed on July 5, 2016. During the testing period, there were no unexplained differences in the root zone files generated from the production and parallel test systems.



In a letter sent on March 4, 2015, NTIA officially requested that Verisign and ICANN work together to develop a proposal on how best to transition NTIA’s administrative role associated with root zone management in a manner that maintains the security, stability, and resiliency of the Internet’s DNS.

In the proposal submitted to NTIA in August 2015, ICANN and Verisign proposed a parallel testing period to confirm that the production Root Zone Management System (RZMS) and the parallel test version of the RZMS (that has had the NTIA authorization step removed) produced identical output for every root zone file published.

The parallel testing would take place over a continuous 90-day period and would be considered successful as long as no unexplained differences in root zone files were identified between the production and parallel test RZMS. In the event that an unexplained difference was found, the issue(s) would be addressed and the 90-day parallel testing period would be restarted.

Before the parallel testing period could begin, ICANN and Verisign spent a period of time making necessary system code changes to remove NTIA’s authorization step and prepare for parallel testing. After the code changes were completed, the parallel testing period started on April 6, 2016. During the 90-day testing period, daily comparison reports of the zone files were published on Verisign’s website. Additionally, monthly summary reports were also made available (below). 

The parallel testing period successfully completed on July 5, 2016. During the testing period, there were no unexplained differences in the root zone files generated from the production and parallel test systems.

The successful completion of the 90-day parallel testing period is a key step in ensuring the continued secure and stable operation of the Internet’s root zone post-transition.

Monthly Reports on RZMS Parallel Testing Progress

Monthly Report Publishing Date
RZMS Parallel Testing Monthly Report - 05Apr16 to 05May16 09-May-16
RZMS Parallel Testing Monthly Report - 06May16 to 05Jun16 23-Jun-16
RZMS Parallel Testing Monthly Report - 05Jun16 to 05Jul16 25-Jul-16


Relevant Links

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."