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Internet Protocol Version 6 Address Space
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xmlns:iana="http://www.iana.org/assignments"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <link rel="stylesheet" href="../_support/iana-registry.css" type="text/css" /> <script type="text/javascript" src="../_support/jquery.js"></script> <script type="text/javascript" src="../_support/sort.js"></script> <title>Internet Protocol Version 6 Address Space</title> </head> <body> <header> <div> <a href="/"> <img src="https://www.iana.org/_img/2022/iana-logo-header.svg" alt="Internet Assigned Numbers Authority" /> </a> </div> </header> <article> <h1>Internet Protocol Version 6 Address Space</h1> <dl> <dt>Last Updated</dt> <dd>2024-09-10</dd> <dt>Note</dt> <dd> <pre>The IPv6 address management function was formally delegated to IANA in December 1995 [<a href="https://www.iana.org/go/rfc1881">RFC1881</a>]. The registration procedure was confirmed with the IETF Chair in March 2010. As stated in [<a href="https://www.iana.org/go/rfc3513">RFC3513</a>], IANA should limit its allocation of IPv6-unicast address space to the range of addresses that start with binary value 001. The rest of the global unicast address space (approximately 85% of the IPv6 address space) is reserved for future definition and use, and is not to be assigned by IANA at this time. While [<a href="https://www.iana.org/go/rfc3513">RFC3513</a>] was obsoleted by [<a href="https://www.iana.org/go/rfc4291">RFC4291</a>], the guidance provided to IANA did not change regarding the allocation of IPv6 unicast addresses. </pre> </dd> <dt>Available Formats</dt> <dd> <a class="altformat" href="ipv6-address-space.xml"><img src="/_img/icons/text-xml.png" /><br />XML</a> <a class="altformat" href="ipv6-address-space.xhtml"><img src="/_img/icons/text-html.png" /><br />HTML</a> <a class="altformat" href="ipv6-address-space.txt"><img src="/_img/icons/text-plain.png" /><br />Plain text</a> </dd> </dl> <dl> <dt>Registration Procedure(s)</dt> <dd> <pre>IESG Approval</pre> </dd> <dt>Available Formats</dt> <dd> <a class="altformat" href="ipv6-address-space-1.csv"><img src="/_img/icons/text-csv.png" /><br />CSV</a> </dd> </dl> <table id="table-ipv6-address-space-1" class="sortable"> <thead> <tr> <th class="sortIPv6">IPv6 Prefix</th> <th>Allocation</th> <th>Reference</th> <th>Notes</th> </tr> </thead> <tbody> <tr> <td>::/8</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td>This range has been partially allocated. See [<a href="https://www.iana.org/assignments/iana-ipv6-special-registry">IANA registry <i>iana-ipv6-special-registry</i></a>] for details. ::/96, formerly defined as the "IPv4-compatible IPv6 address" prefix, was deprecated by [<a href="https://www.iana.org/go/rfc4291">RFC4291</a>].</td> </tr> <tr> <td>100::/8</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td>This range has been partially allocated. See [<a href="https://www.iana.org/assignments/iana-ipv6-special-registry">IANA registry <i>iana-ipv6-special-registry</i></a>] for details.</td> </tr> <tr> <td>200::/7</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc4048">RFC4048</a>]</td> <td>Deprecated as of December 2004 [<a href="https://www.iana.org/go/rfc4048">RFC4048</a>]. Formerly an OSI NSAP-mapped prefix set [<a href="https://www.iana.org/go/rfc4548">RFC4548</a>].</td> </tr> <tr> <td>400::/6</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>800::/5</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>1000::/4</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>2000::/3</td> <td>Global Unicast</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td>The IPv6 Unicast space encompasses the entire IPv6 address range with the exception of ff00::/8, per [<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]. IANA unicast address assignments are currently limited to the IPv6 unicast address range of 2000::/3. IANA assignments from this block are registered in [<a href="https://www.iana.org/assignments/ipv6-unicast-address-assignments">IANA registry <i>ipv6-unicast-address-assignments</i></a>]. </td> </tr> <tr> <td>4000::/3</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td>This range has been partially allocated. See [<a href="https://www.iana.org/assignments/iana-ipv6-special-registry">IANA registry <i>iana-ipv6-special-registry</i></a>] for details. 5f00::/8 (with 3ffe::/16, as noted at [<a href="https://www.iana.org/assignments/ipv6-unicast-address-assignments">IANA registry <i>ipv6-unicast-address-assignments</i></a>]) was used for the 6bone, but returned [<a href="https://www.iana.org/go/rfc5156">RFC5156</a>].</td> </tr> <tr> <td>6000::/3</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>8000::/3</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>a000::/3</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>c000::/3</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>e000::/4</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>f000::/5</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>f800::/6</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>fc00::/7</td> <td>Unique Local Unicast</td> <td>[<a href="https://www.iana.org/go/rfc4193">RFC4193</a>]</td> <td>See [<a href="https://www.iana.org/assignments/iana-ipv6-special-registry">IANA registry <i>iana-ipv6-special-registry</i></a>] for details.</td> </tr> <tr> <td>fe00::/9</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td></td> </tr> <tr> <td>fe80::/10</td> <td>Link-Scoped Unicast</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td>See [<a href="https://www.iana.org/assignments/iana-ipv6-special-registry">IANA registry <i>iana-ipv6-special-registry</i></a>] for details.</td> </tr> <tr> <td>fec0::/10</td> <td>Reserved by IETF</td> <td>[<a href="https://www.iana.org/go/rfc3879">RFC3879</a>]</td> <td>Deprecated by [<a href="https://www.iana.org/go/rfc3879">RFC3879</a>] in September 2004. Formerly a Site-Local scoped address prefix.</td> </tr> <tr> <td>ff00::/8</td> <td>Multicast</td> <td>[<a href="https://www.iana.org/go/rfc3513">RFC3513</a>][<a href="https://www.iana.org/go/rfc4291">RFC4291</a>]</td> <td>See [<a href="https://www.iana.org/assignments/ipv6-multicast-addresses">IANA registry <i>ipv6-multicast-addresses</i></a>] for details.</td> </tr> </tbody> </table> </article> <footer> <div> <a href="https://www.iana.org/help/licensing-terms">Licensing Terms</a> </div> </footer> </body> </html>