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<p class="MsoNormal">Dear colleagues,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">ICANN has opened a public comment period on a research study titled "Controlled Interruption IPv6 Research Study". The study focuses on extending ICANN's "controlled interruption" mechanism, previously implemented using only the IPv4 address
127.0.53.53 into the IPv6 realm, given the growing adoption of IPv6 (> 40 % of hosts). The public comment period runs from 20 October 2025 to 22 December 2025:
<a href="https://www.icann.org/en/public-comment/proceeding/name-collision-ipv6-research-study-20-10-2025" target="_blank">
https://www.icann.org/en/public-comment/proceeding/name-collision-ipv6-research-study-20-10-2025</a>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Controlled interruption is a phase in the establishment of a new generic top-level domain (gTLD) that is designed to reduce the risk of name collision. During controlled interruption, certain DNS resource records, designed to interrupt
resolution processes, are temporarily published at and below the gTLD name. The content of these DNS records is intended to minimize any harm that arises from such interruption.
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This study produces an initial list of candidate prefixes, followed by technical tests of multiple applications on popular end-user operating systems. The aim was to identify candidate addresses where DNS lookups returning that address
did not result in any unintended external network traffic. A preferred candidate that met these criteria was identified: ffff:127.0.53.53, which is the IPV6 mapping of the original IPv4 controlled interruption address.
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This mailing list is being alerted to request input on this topic. While there will undoubtedly be valuable discussions on this list around various aspects of this proposal, ICANN requests that specific feedback (from individuals or the
group as a whole) is ultimately provided directly into the public comment website.</p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="mso-ligatures:none">-- <o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-ligatures:none">Francisco.<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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