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  <front>
    <title abbrev="SPICE GLUE">GLobal Unique Enterprise (GLUE) Identifiers</title>
    <seriesInfo name="Internet-Draft" value="draft-ietf-spice-glue-id-04"/>
    <author fullname="Brent W. Zundel">
      <organization/>
      <address>
        <postal>
          <country>United States</country>
        </postal>
        <email>brent.zundel@gmail.com</email>
      </address>
    </author>
    <author fullname="Pamela Dingle">
      <organization>Microsoft Corporation</organization>
      <address>
        <postal>
          <country>United States</country>
        </postal>
        <email>pamela.dingle@microsoft.com</email>
      </address>
    </author>
    <author initials="M. B." surname="Jones" fullname="Michael B. Jones">
      <organization>Self-Issued Consulting</organization>
      <address>
        <postal>
          <country>United States</country>
        </postal>
        <email>michael_b_jones@hotmail.com</email>
        <uri>https://self-issued.info/</uri>
      </address>
    </author>
    <date year="2026" month="January" day="28"/>
    <area>Security</area>
    <workgroup>Secure Patterns for Internet CrEdentials</workgroup>
    <keyword>URI</keyword>
    <keyword>URN</keyword>
    <keyword>Enterprise</keyword>
    <keyword>Entity Identifiers</keyword>
    <abstract>
      <?line 74?>

<t>This specification establishes a URN namespace for
GLobal Unique Enterprise (GLUE) Identifiers.
This enables URN identifiers to be used for businesses and organizations.
It enables organizational identities from existing authorities to be represented within this URN namespace.</t>
    </abstract>
    <note removeInRFC="true">
      <name>About This Document</name>
      <t>
        The latest revision of this draft can be found at <eref target="https://ietf-wg-spice.github.io/draft-ietf-spice-glue-id/draft-ietf-spice-glue-id.html"/>.
        Status information for this document may be found at <eref target="https://datatracker.ietf.org/doc/draft-ietf-spice-glue-id/"/>.
      </t>
      <t>
        Discussion of this document takes place on the
        Secure Patterns for Internet CrEdentials Working Group mailing list (<eref target="mailto:spice@ietf.org"/>),
        which is archived at <eref target="https://mailarchive.ietf.org/arch/browse/spice/"/>.
        Subscribe at <eref target="https://www.ietf.org/mailman/listinfo/spice/"/>.
      </t>
      <t>Source for this draft and an issue tracker can be found at
        <eref target="https://github.com/ietf-wg-spice/draft-ietf-spice-glue-id"/>.</t>
    </note>
  </front>
  <middle>
    <?line 81?>

<section anchor="introduction">
      <name>Introduction</name>
      <t>There are a myriad of entity identifier types for businesses and organizations.
With the increasing use of digital credentials, there is a need for a common
methodology for expressing these identifiers such that claims about and by such
entities can be made in a consistent and interoperable manner.</t>
      <t>This specification establishes a URN namespace that standardizes the expression of
existing organizational entity identifiers by providing a common representation format.
It also establishes a registry for managing how existing organizational entity
identification mechanisms relate to this namespace.</t>
      <t>Any organizational entity identifier whose identification mechanism has been registered
as an Authority Identifier in the registry may be represented as a GLUE URI.</t>
      <section anchor="requirements-notation-and-conventions">
        <name>Requirements Notation and Conventions</name>
        <t>The key words "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>", "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL
NOT</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>", "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>",
"<bcp14>MAY</bcp14>", and "<bcp14>OPTIONAL</bcp14>" in this document are to be interpreted as
described in BCP 14 <xref target="RFC2119"/> <xref target="RFC8174"/> when, and only when, they
appear in all capitals, as shown here.</t>
        <?line -18?>

</section>
      <section anchor="terminology">
        <name>Terminology</name>
        <t>This specification uses the following terms:</t>
        <dl>
          <dt>GLUE URI:</dt>
          <dd>
            <t>a URI that uses the GLUE URN namespace established in this specification.</t>
          </dd>
          <dt>External Authority:</dt>
          <dd>
            <t>an organization that allocates External Identifiers for GLUE URIs using the Authority Identifier(s) over which they have jurisdiction.</t>
          </dd>
          <dt>Authority Identifier:</dt>
          <dd>
            <t>identifier for the External Authority responsible for assigning the External Identifier used in GLUE URIs.</t>
          </dd>
          <dt>External Identifier:</dt>
          <dd>
            <t>identifier assigned by an External Authority to identify a particular organization within GLUE URNs over which it has jurisdiction.</t>
          </dd>
        </dl>
      </section>
    </section>
    <section anchor="core-concepts">
      <name>Core Concepts</name>
      <t>Every GLUE URI <bcp14>MUST</bcp14>
contain the following components:</t>
      <ul spacing="normal">
        <li>
          <t>The Authority Identifier</t>
        </li>
        <li>
          <t>The External Identifier</t>
        </li>
      </ul>
      <section anchor="uniqueness-and-namespacing">
        <name>Uniqueness and Namespacing</name>
        <t>Each GLUE URI <bcp14>MUST</bcp14> be globally unique.</t>
        <t>It is assumed that most registered organizational entity identification schemes
already handle any necessary namespacing as part of the External Identifier.
However, if collisions are possible within the set of possible external
identifiers for an Authority Identifier scheme, then further namespacing is
necessary at the GLUE URI level. Such namespacing <bcp14>MUST</bcp14> be done on the Authority
Identifier. The combination of the namespacing and the authority <bcp14>MUST</bcp14> result in
a unique Authority Identifier.</t>
        <t>For example, assume there is an External Authority FEA that provides identifiers
for organizations in Singapore and South Korea. The identifiers issued in
Singapore are unique within Singapore, and the identifiers issued in South Korea
are unique within South Korea, but there is no guarantee that an organization in
Singapore will not be assigned the same identifier as an organization in South
Korea. Upon registration of FEA as an Authority Identifier, it would be
necessary to separately register two different Authority Identifiers (e.g.,
FEA-SG and FEA-KR) to provide differentiation between the two sets of External
Identifiers.</t>
      </section>
    </section>
    <section anchor="glue-uris">
      <name>GLUE URIs</name>
      <t>GLUE URIs comply with <xref target="RFC3986"/>.
They begin with <tt>urn:glue:</tt> and are followed by an Authority Identifier,
a colon character (":"), and the External Identifier allocated by the authority.</t>
      <t>Authority Identifiers consist of a sequence of characters beginning with a
letter and followed by any combination of letters, digits, plus ("+"), period
("."), or hyphen ("-").
Although Authority Identifiers are case-insensitive, the canonical form is
lowercase and documents that specify Authority Identifiers must do so with
lowercase letters. An implementation should accept uppercase letters as
equivalent to lowercase in Authority Identifier names (e.g., allow "EXAMPLE" as
well as "example") for the sake of robustness but should only produce lowercase
Authority Identifier names for consistency. There is a limit of 50 characters
for the length of an Authority Identifier.
The ABNF <xref target="RFC5234"/> for Authority Identifiers is:</t>
      <t><tt>
authority-identifier = ALPHA *49( ALPHA / DIGIT / "+" / "-" / "." )
</tt></t>
      <t>External Identifiers consist of a sequence of characters beginning with a letter
or digit or hyphen ("-") and followed by any combination of letters, digits,
plus ("+"), period ("."), or hyphen ("-").
A digit or hyphen is allowed as the first character to permit the case where the
External Identifier is the representation of a number. It is specific to the
Authority Identifier whether the External Identifiers are case-insensitive or
case-sensitive. When they are case-insensitive, the canonical form is lowercase
and documents that specify External Identifiers must do so with lowercase
letters. There is a limit of 1000 characters for an External Identifier.
The ABNF <xref target="RFC5234"/> for External Identifiers is:</t>
      <t><tt>
external-identifier = ( ALPHA / DIGIT / "-" ) *999( ALPHA / DIGIT / "+" / "-" / "." )
</tt></t>
      <t>Combining these, the ABNF <xref target="RFC5234"/> for a GLUE URI is:</t>
      <t><tt>
glue-uri = "urn:glue:" authority-identifier ":" external-identifier
</tt></t>
      <t>For example, the following is a GLUE URI using the Authority Identifier "pen"
and the External Identifier "1.3.6.1.4.1.32473":</t>
      <t><tt>
urn:glue:pen:1.3.6.1.4.1.32473
</tt></t>
      <t>The Authority Identifier <bcp14>MUST</bcp14> be registered in the GLUE URI Authority Identifier registry
defined in <xref target="GLUE-URN"/>.
The External Identifier <bcp14>MUST</bcp14> be the identifier assigned to the organization
by the External Authority.</t>
    </section>
    <section anchor="authority-identifiers">
      <name>GLUE Authority Identifiers</name>
      <t>This section defines the following GLUE Authority Identifiers.</t>
      <table>
        <thead>
          <tr>
            <th align="left">Organization</th>
            <th align="left">Authority Identifier</th>
            <th align="left">External Authority Specification</th>
          </tr>
        </thead>
        <tbody>
          <tr>
            <td align="left">GS1</td>
            <td align="left">gln</td>
            <td align="left">https://www.gs1.org/standards/id-keys/gln</td>
          </tr>
          <tr>
            <td align="left">GLEIF</td>
            <td align="left">lei</td>
            <td align="left">https://www.iso.org/standard/78829.html</td>
          </tr>
          <tr>
            <td align="left">Dun &amp; Bradstreet</td>
            <td align="left">duns</td>
            <td align="left">https://www.dnb.com/duns.html</td>
          </tr>
          <tr>
            <td align="left">Private Enterprise Numbers</td>
            <td align="left">pen</td>
            <td align="left">https://www.iana.org/assignments/enterprise-numbers</td>
          </tr>
        </tbody>
      </table>
      <t>They are registered in the GLUE Authority Identifier URN Registry in <xref target="GLUE-URN"/>.</t>
      <section anchor="note-about-lei-urns">
        <name>Note about LEI URNs</name>
        <t>Readers should be aware that <xref target="LEI-IANA"/> registers a URN namespace for LEIs. This
means that LEIs can be represented as URNs in at least two ways. For example,
"urn:lei:INR2EJN1ERAN0W5ZP974" is equivalent to "urn:glue:lei:INR2EJN1ERAN0W5ZP974".</t>
      </section>
    </section>
    <section anchor="security-considerations">
      <name>Security Considerations</name>
      <t>There are no additional security considerations beyond those already inherent to
using URNs.
Security considerations for URNs can be found in <xref target="RFC2141"/>.</t>
    </section>
    <section anchor="privacy-considerations">
      <name>Privacy Considerations</name>
      <section anchor="private-identifiers-as-corporate-identifiers">
        <name>Private Identifiers as Corporate Identifiers</name>
        <t>There are some corporate identifiers that make use of personal identifiers. For
example, this is the case for some registered sole-proprietor businesses in the
United States, where the Tax ID may be the same as the Social Security Number
(SSN) of the business owner. Where the Tax ID uniquely identifies the business,
the SSN uniquely identifies an individual.</t>
        <t>It is possible for such business identifiers to be represented as GLUE URIs. An
identifier's expression as a GLUE URI does not change the privacy
characteristics of that identifier. The same cautions and concerns need to be
taken with the GLUE URI representation as with the original identifier.</t>
        <t>Implementers storing or evaluating GLUE URIs are encouraged to be aware the
privacy characteristics of each identification scheme represented by an
Authority Identifier and to appropriately handle any GLUE URI which violates
privacy policies.</t>
      </section>
    </section>
    <section anchor="iana-considerations">
      <name>IANA Considerations</name>
      <t>This section establishes a registry and populates it with its initial contents.
The following registration procedure is used for the
registry established by this specification.</t>
      <t>Values are registered on a Specification Required <xref target="RFC8126"/>
basis after a two-week review period on the spice-ext-review@ietf.org
mailing list, on the advice of one or more Designated Experts.
However, to allow for the allocation of values prior to publication
of the final version of a specification,
the Designated Experts may approve registration once they are satisfied
that the specification will be completed and published.
However, if the specification is not completed and published
in a timely manner, as determined by the Designated Experts,
the Designated Experts may request that IANA withdraw the registration.</t>
      <t>Registration requests sent to the mailing list for review should use
an appropriate subject
(e.g., "Request to register URN urn:glue:example").</t>
      <t>Within the review period, the Designated Experts will either approve or deny
the registration request, communicating this decision to the review list and IANA.
Denials should include an explanation and, if applicable,
suggestions as to how to make the request successful.
The IANA escalation process can be initiated by the party requesting registration
when the Designated Experts are not responsive within 14 days.</t>
      <t>Criteria that should be applied by the Designated Experts includes
determining whether the proposed registration duplicates existing functionality,
determining whether it is likely to be of general applicability
or whether it is useful only for a single application,
and whether the registration makes sense.</t>
      <t>IANA must only accept registry updates from the Designated Experts and should direct
all requests for registration to the review mailing list.</t>
      <t>It is suggested that multiple Designated Experts be appointed who are able to
represent the perspectives of different applications using this specification,
in order to enable broadly-informed review of registration decisions.
In cases where a registration decision could be perceived as
creating a conflict of interest for a particular Expert,
that Expert should defer to the judgment of the other Experts.</t>
      <t>The reason for the use of the mailing list is to enable
public review of registration requests, enabling both Designated Experts
and other interested parties to provide feedback on proposed registrations.
The reason to allow the Designated Experts to
allocate values prior to publication as a final specification is to enable
giving authors of specifications proposing registrations
the benefit of review by the Designated Experts
before the specification is completely done,
so that if problems are identified, the authors can iterate and fix them
before publication of the final specification.</t>
      <section anchor="GLUE-URN">
        <name>GLUE Authority Identifier URN Registry</name>
        <t>This specification establishes the
IANA "GLUE Authority Identifier URN" registry
creating a URN namespace for Authority Identifiers for
GLobal Unique Enterprise (GLUE) Identifiers.</t>
        <t>Each entry registers the URN for an Authority Identifier within the
"urn:glue:" namespace.
The organization responsible for the Authority Identifier is recorded.</t>
        <t>IANA is requested to create the
"GLobal Unique Enterprise (GLUE) Identifiers"
registry group located at
https://www.iana.org/assignments/glue-identifiers/
and place this registry there.</t>
        <section anchor="registration-template">
          <name>Registration Template</name>
          <dl>
            <dt>Authority Identifier:</dt>
            <dd>
              <t>identifier for the External Authority responsible for assigning the External Identifier used in GLUE URIs.
This identifier
is not case sensitive and any letters <bcp14>MUST</bcp14> be expressed in lowercase characters.
It <bcp14>MUST</bcp14> consist of a sequence of characters with a mazimum length of 50,
beginning with a letter and followed by any combination of
letters, digits, plus ("+"), period ("."), or hyphen ("-").</t>
            </dd>
            <dt>URN:</dt>
            <dd>
              <t>The URN within the "urn:glue:" namespace
consisting of "urn:glue:" followed by
the Authority Identifier.</t>
            </dd>
            <dt>Organization:</dt>
            <dd>
              <t>The organization responsible for the Authority Identifier.</t>
            </dd>
            <dt>Change Controller:</dt>
            <dd>
              <t>For IETF stream RFCs, use "IETF".
For others, give the name of the responsible party.
Other details (e.g., postal address, e-mail address, home page URI) may also be included.</t>
            </dd>
            <dt>Specification Document(s):</dt>
            <dd>
              <t>Reference to the document or documents that specify the Authority Identifier to be registered,
preferably including URLs that can be used to retrieve the documents.
An indication of the relevant sections may also be included, but is not required.</t>
            </dd>
          </dl>
        </section>
        <section anchor="initial-registry-contents">
          <name>Initial Registry Contents</name>
          <section anchor="gln">
            <name>gln</name>
            <ul spacing="normal">
              <li>
                <t>Authority Identifier: gln</t>
              </li>
              <li>
                <t>URN: urn:glue:gln</t>
              </li>
              <li>
                <t>Organization: GS1</t>
              </li>
              <li>
                <t>Change Controller: IETF</t>
              </li>
              <li>
                <t>Specification Document(s): <xref target="authority-identifiers"/> of this specification, <xref target="GLN"/></t>
              </li>
            </ul>
          </section>
          <section anchor="lei">
            <name>lei</name>
            <ul spacing="normal">
              <li>
                <t>Authority Identifier: lei</t>
              </li>
              <li>
                <t>URN: urn:glue:lei</t>
              </li>
              <li>
                <t>Organization: GLEIF</t>
              </li>
              <li>
                <t>Change Controller: IETF</t>
              </li>
              <li>
                <t>Specification Document(s): <xref target="authority-identifiers"/> of this specification, <xref target="LEI"/>, <xref target="LEI-IANA"/></t>
              </li>
            </ul>
          </section>
          <section anchor="duns">
            <name>duns</name>
            <ul spacing="normal">
              <li>
                <t>Authority Identifier: duns</t>
              </li>
              <li>
                <t>URN: urn:glue:duns</t>
              </li>
              <li>
                <t>Organization: Dun &amp; Bradstreet</t>
              </li>
              <li>
                <t>Change Controller: IETF</t>
              </li>
              <li>
                <t>Specification Document(s): <xref target="authority-identifiers"/> of this specification, <xref target="DUNS"/></t>
              </li>
            </ul>
          </section>
          <section anchor="pen">
            <name>pen</name>
            <ul spacing="normal">
              <li>
                <t>Authority Identifier: pen</t>
              </li>
              <li>
                <t>URN: urn:glue:pen</t>
              </li>
              <li>
                <t>Organization: Private Enterprise Numbers</t>
              </li>
              <li>
                <t>Change Controller: IETF</t>
              </li>
              <li>
                <t>Specification Document(s): <xref target="authority-identifiers"/> of this specification, <xref target="PEN"/>, <xref target="RFC9371"/></t>
              </li>
            </ul>
          </section>
        </section>
      </section>
    </section>
  </middle>
  <back>
    <references anchor="sec-combined-references">
      <name>References</name>
      <references anchor="sec-normative-references">
        <name>Normative References</name>
        <reference anchor="RFC3986">
          <front>
            <title>Uniform Resource Identifier (URI): Generic Syntax</title>
            <author fullname="T. Berners-Lee" initials="T." surname="Berners-Lee"/>
            <author fullname="R. Fielding" initials="R." surname="Fielding"/>
            <author fullname="L. Masinter" initials="L." surname="Masinter"/>
            <date month="January" year="2005"/>
            <abstract>
              <t>A Uniform Resource Identifier (URI) is a compact sequence of characters that identifies an abstract or physical resource. This specification defines the generic URI syntax and a process for resolving URI references that might be in relative form, along with guidelines and security considerations for the use of URIs on the Internet. The URI syntax defines a grammar that is a superset of all valid URIs, allowing an implementation to parse the common components of a URI reference without knowing the scheme-specific requirements of every possible identifier. This specification does not define a generative grammar for URIs; that task is performed by the individual specifications of each URI scheme. [STANDARDS-TRACK]</t>
            </abstract>
          </front>
          <seriesInfo name="STD" value="66"/>
          <seriesInfo name="RFC" value="3986"/>
          <seriesInfo name="DOI" value="10.17487/RFC3986"/>
        </reference>
        <reference anchor="GLN" target="https://www.gs1.org/standards/id-keys/gln">
          <front>
            <title>Global Location Nymber (GLN)</title>
            <author>
              <organization/>
            </author>
            <date>n.d.</date>
          </front>
        </reference>
        <reference anchor="DUNS" target="https://www.dnb.com/duns.html">
          <front>
            <title>D-U-N-S Numbers</title>
            <author>
              <organization/>
            </author>
            <date>n.d.</date>
          </front>
        </reference>
        <reference anchor="LEI" target="https://www.iso.org/standard/78829.html">
          <front>
            <title>Legal Entity Identifier (LEI)</title>
            <author>
              <organization/>
            </author>
            <date>n.d.</date>
          </front>
        </reference>
        <reference anchor="PEN" target="https://www.iana.org/assignments/enterprise-numbers">
          <front>
            <title>Private Enterprise Numbers</title>
            <author>
              <organization/>
            </author>
            <date>n.d.</date>
          </front>
        </reference>
        <reference anchor="RFC2119">
          <front>
            <title>Key words for use in RFCs to Indicate Requirement Levels</title>
            <author fullname="S. Bradner" initials="S." surname="Bradner"/>
            <date month="March" year="1997"/>
            <abstract>
              <t>In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.</t>
            </abstract>
          </front>
          <seriesInfo name="BCP" value="14"/>
          <seriesInfo name="RFC" value="2119"/>
          <seriesInfo name="DOI" value="10.17487/RFC2119"/>
        </reference>
        <reference anchor="RFC8174">
          <front>
            <title>Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words</title>
            <author fullname="B. Leiba" initials="B." surname="Leiba"/>
            <date month="May" year="2017"/>
            <abstract>
              <t>RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings.</t>
            </abstract>
          </front>
          <seriesInfo name="BCP" value="14"/>
          <seriesInfo name="RFC" value="8174"/>
          <seriesInfo name="DOI" value="10.17487/RFC8174"/>
        </reference>
      </references>
      <references anchor="sec-informative-references">
        <name>Informative References</name>
        <reference anchor="RFC2141">
          <front>
            <title>URN Syntax</title>
            <author fullname="R. Moats" initials="R." surname="Moats"/>
            <date month="May" year="1997"/>
            <abstract>
              <t>Uniform Resource Names (URNs) are intended to serve as persistent, location-independent, resource identifiers. This document sets forward the canonical syntax for URNs. [STANDARDS-TRACK]</t>
            </abstract>
          </front>
          <seriesInfo name="RFC" value="2141"/>
          <seriesInfo name="DOI" value="10.17487/RFC2141"/>
        </reference>
        <reference anchor="RFC8126">
          <front>
            <title>Guidelines for Writing an IANA Considerations Section in RFCs</title>
            <author fullname="M. Cotton" initials="M." surname="Cotton"/>
            <author fullname="B. Leiba" initials="B." surname="Leiba"/>
            <author fullname="T. Narten" initials="T." surname="Narten"/>
            <date month="June" year="2017"/>
            <abstract>
              <t>Many protocols make use of points of extensibility that use constants to identify various protocol parameters. To ensure that the values in these fields do not have conflicting uses and to promote interoperability, their allocations are often coordinated by a central record keeper. For IETF protocols, that role is filled by the Internet Assigned Numbers Authority (IANA).</t>
              <t>To make assignments in a given registry prudently, guidance describing the conditions under which new values should be assigned, as well as when and how modifications to existing values can be made, is needed. This document defines a framework for the documentation of these guidelines by specification authors, in order to assure that the provided guidance for the IANA Considerations is clear and addresses the various issues that are likely in the operation of a registry.</t>
              <t>This is the third edition of this document; it obsoletes RFC 5226.</t>
            </abstract>
          </front>
          <seriesInfo name="BCP" value="26"/>
          <seriesInfo name="RFC" value="8126"/>
          <seriesInfo name="DOI" value="10.17487/RFC8126"/>
        </reference>
        <reference anchor="RFC5234">
          <front>
            <title>Augmented BNF for Syntax Specifications: ABNF</title>
            <author fullname="D. Crocker" initials="D." role="editor" surname="Crocker"/>
            <author fullname="P. Overell" initials="P." surname="Overell"/>
            <date month="January" year="2008"/>
            <abstract>
              <t>Internet technical specifications often need to define a formal syntax. Over the years, a modified version of Backus-Naur Form (BNF), called Augmented BNF (ABNF), has been popular among many Internet specifications. The current specification documents ABNF. It balances compactness and simplicity with reasonable representational power. The differences between standard BNF and ABNF involve naming rules, repetition, alternatives, order-independence, and value ranges. This specification also supplies additional rule definitions and encoding for a core lexical analyzer of the type common to several Internet specifications. [STANDARDS-TRACK]</t>
            </abstract>
          </front>
          <seriesInfo name="STD" value="68"/>
          <seriesInfo name="RFC" value="5234"/>
          <seriesInfo name="DOI" value="10.17487/RFC5234"/>
        </reference>
        <reference anchor="RFC9371">
          <front>
            <title>Registration Procedures for Private Enterprise Numbers (PENs)</title>
            <author fullname="A. Baber" initials="A." surname="Baber"/>
            <author fullname="P. Hoffman" initials="P." surname="Hoffman"/>
            <date month="March" year="2023"/>
            <abstract>
              <t>This document describes how Private Enterprise Numbers (PENs) are registered by IANA. It shows how to request a new PEN and how to modify a current PEN. It also gives a brief overview of PEN uses.</t>
            </abstract>
          </front>
          <seriesInfo name="RFC" value="9371"/>
          <seriesInfo name="DOI" value="10.17487/RFC9371"/>
        </reference>
        <reference anchor="LEI-IANA" target="https://www.iana.org/assignments/urn-formal/lei">
          <front>
            <title>LEI Namespace Identifier</title>
            <author>
              <organization/>
            </author>
            <date>n.d.</date>
          </front>
        </reference>
      </references>
    </references>
    <?line 401?>

<section numbered="false" anchor="acknowledgments">
      <name>Acknowledgments</name>
      <t>Alexander (A.J.) Stein
and
Martin Thomson
contributed to this specification.</t>
    </section>
    <section numbered="false" anchor="document-history">
      <name>Document History</name>
      <t>-04</t>
      <ul spacing="normal">
        <li>
          <t>Applied review suggestions from Martin Thomson, specifically:
          </t>
          <ul spacing="normal">
            <li>
              <t>Added references for each registered Authority Identifier.</t>
            </li>
            <li>
              <t>Added size limits for Authority Identifiers and External Identifiers.</t>
            </li>
            <li>
              <t>Added a note about LEI URNs.</t>
            </li>
          </ul>
        </li>
      </ul>
      <t>-03</t>
      <ul spacing="normal">
        <li>
          <t>Use the urn:glue URN namespace and delete the urn:ietf:spice URN namespace.</t>
        </li>
        <li>
          <t>Addressed early IANA feedback.</t>
        </li>
      </ul>
      <t>-02</t>
      <ul spacing="normal">
        <li>
          <t>Improved several descriptions in the specification.</t>
        </li>
      </ul>
      <t>-01</t>
      <ul spacing="normal">
        <li>
          <t>Updated Brent's affiliation.</t>
        </li>
      </ul>
      <t>-00</t>
      <ul spacing="normal">
        <li>
          <t>Initial working group draft, based on draft-zundel-spice-glue-id-02</t>
        </li>
      </ul>
    </section>
  </back>
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</rfc>
