Object Search for the Extensible Provisioning Protocol (EPP)
draft-sattler-kolker-epp-object-search-00

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Authors Tobias Sattler  , Jody Kolker 
Last updated 2021-12-21
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Internet Engineering Task Force (IETF)                        T. Sattler
Internet-Draft
Intended status: Standards Track                               J. Kolker
Expires: January 3, 2022                                    GoDaddy Inc.
                                                       December 21, 2021

     Object Search for the Extensible Provisioning Protocol (EPP)
                 draft-sattler-kolker-epp-object-search-00

Abstract

   This document describes an Extensible Provisioning Protocol (EPP)
   extension called "Object Search", which EPP clients use to search and
   list EPP objects stored by EPP servers.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
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   material or to cite them other than as "work in progress".

   This Internet-Draft will expire on January 3, 2022.

Copyright Notice

   Copyright (c) 2021 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Terminology and Definitions . . . . . . . . . . . . . . .   3
   2.  Migrating to Newer Versions of This Extension . . . . . . . .   4
   3.  Object Attributes . . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  Object Search Elements  . . . . . . . . . . . . . . . . .   4
   4.  EPP Command Mapping . . . . . . . . . . . . . . . . . . . . .   5
     4.1.  EPP Query Commands  . . . . . . . . . . . . . . . . . . .   5
       4.1.1.  EPP <info> Command  . . . . . . . . . . . . . . . . .   5
       4.1.1.1.  Object Search Domains . . . . . . . . . . . . . . .   5
       4.1.1.2.  Object Search Contacts  . . . . . . . . . . . . . .   7
       4.1.1.3.  Object Search Hosts . . . . . . . . . . . . . . . .   8
     4.2.  EPP Transform Commands  . . . . . . . . . . . . . . . . .  10
   5.  Formal Syntax . . . . . . . . . . . . . . . . . . . . . . . .  10
     5.1.  Object Search EPP Mapping Schema  . . . . . . . . . . . .  10
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  13
     6.1.  XML Namespace . . . . . . . . . . . . . . . . . . . . . .  13
     6.2.  EPP Extension Registry  . . . . . . . . . . . . . . . . .  13
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   8.  Implementation Status . . . . . . . . . . . . . . . . . . . .  14
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  14
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  15
   Appendix A.  Change History . . . . . . . . . . . . . . . . . . .  15
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15
     
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1.  Introduction

   The Extensible Provisioning Protocol (EPP), as defined in [RFC5730],
   is a protocol whose original motivation is to provide a standard
   Internet domain name registration protocol for use between registries
   and registrars.
   
   Registrars can transform EPP objects either with <create>, <delete>,
   <renew>, <transfer>, or <update> according to [RFC5730]. They are
   usually responsible for maintaining their inventory themselves.
   
   Due to various reasons, such as consolidation of registrars,
   migrations, development of new management systems, etc., it may
   happen that a registrar has lost track of its inventory.
   
   EPP already provides query capabilities with <check> and <info>, but
   those are limited to looking up exact strings. Therefore, it is
   desirable to implement a search functionality via EPP to find any
   forgotten or orphaned objects.

   This document describes an extension mapping for version 1.0 of the
   EPP to provide a mechanism by which EPP clients can search and list
   EPP objects stored by EPP servers.

1.1.  Terminology and Definitions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   XML [W3C.REC-xml11-20060816] is case-sensitive. Unless stated
   otherwise, XML specification and examples provided in this document
   MUST be interpreted in the character case presented in order to
   develop a conforming implementation.

   "object-search" is used as an abbreviation for "urn:ietf:params:xml:
   ns:epp:object-search-0.1". The XML namespace prefix "object-search"
   is used, but implementations MUST NOT depend on it. Instead, they are
   to employ a proper namespace-aware XML parser and serializer to
   interpret and output the XML documents.
   
   In examples, "C:" represents lines sent by a protocol client, and
   "S:" represents lines returned by a protocol server. Indentation and
   white space in examples are provided only to illustrate element
   relationships and are not a required feature of this protocol.

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2.  Migrating to Newer Versions of This Extension

   Servers that implement this extension SHOULD provide a way for
   clients to progressively update their implementations when a new
   version of the extension is deployed.  A newer version of the
   extension is expected to use an XML namespace with a higher version
   number than the prior versions.
   
   Servers SHOULD (for a temporary migration period up to server policy)
   provide support for older versions of the extension in parallel to
   the newest version and allow clients to execute their preferred
   version of the <info> command based on the object search <objURI>
   elements of the server <greeting>. The version of the object search
   <info> response MUST match the version of the object search <info>
   command executed by the server.

3.  Object Attributes

3.1.  Object Search Elements
   
   The minimum character for a search pattern and the the limit for the
   search results is up to server policy.

   <object-search:domain>
     The search pattern for the domain object; the attribute "type" is
     REQUIRED and MUST either be "name", "contact", "host", "status",
     "crDate", "upDate", "exDate", or "trDate". The attribute "filter"
     REQUIRED and MUST be present to identify the filter and MUST either
     be "exact", "begins", "ends", or "contains".
   
   <object-search:host>
     The search pattern for the host object; the attribute "type" is
     REQUIRED and MUST either be "name", "ipv4", or "ipv6". The
     attribute "filter" is REQUIRED and MUST be present to identify the
     filter and MUST either be "exact", "begins", "ends", or "contains".

   <object-search:contact>
     The search pattern for the contact object; the attribute "type" is
     REQUIRED and MUST either be "id", "name", "orga", "street", "city",
     "state", "postcode", "email", "voice", "fax", or "country". The
     attribute "filter" is REQUIRED and MUST be present to identify the
     filter and MUST either be "exact", "begins", "ends", or "contains".

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4.  EPP Command Mapping

   A detailed description of the EPP syntax and semantics can be found
   in the EPP core protocol specification [RFC5730]. The command
   mappings described here are specifically used to search for objects
   and object mapping.

4.1.  EPP Query Commands

   EPP [RFC5730] provides four commands to retrieve object information:
   <check> to determine if an object is known to the server, <info> to
   retrieve detailed information associated with an object, <poll> to
   discover and retrieve service messages, and <transfer> to retrieve
   object transfer status information.
   
   This extension does not add any elements to EPP <check>, <poll>, and
   <transfer> commands or responses.

4.1.1.  EPP <info> Command

   EPP provides the <info> command that is used to looking up objects.
   In addition to the standard EPP command elements, the <info> command
   MUST contain a <object-search:info> element that allows objects to be
   searched.
   
   The <object-search:info> element MUST contain a child element. It is
   either the <object-search:domain> child element, described in Section
   4.1.1.1, to search domains, the <object-search:contact> child
   element, described in Section 4.1.1.2, to search contacts, or the
   <object-search:host> child element, described in Section 4.1.1.3, to
   search hosts.

4.1.1.1.  Object Search Domains

   A search for domain objects can be performed by using the <info>
   command with the <object-search> element and the
   <object-search:domain> child element, defined in Section 3.1.

   Example to search for a domain object in an <info> command.
   
   C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
   C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
   C:  <command>
   C:    <info>
   C:      <object-search:info xmlns:object-search=
   C:        "urn:ietf:params:xml:ns:epp:object-search-0.1">
   C:        <object-search:domain type="name" filter="begins">example
   C:        </object-search:domain>
   C:      </object-search:info>
   C:    </info>
   C:    <clTRID>ABC-12345</clTRID>
   C:  </command>
   C:</epp>

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   When an <info> command has been processed successfully, the EPP
   <resData> element MUST contain a child <object-search:infData>
   element that identifies the object search namespace. The
   <object-search:infData> element contains the <object-search:list>
   element with zero or more <object-search:item> child elements. The
   "total" attribute is REQUIRED and MUST contain the total number of
   the search result. This allows the client to determine if the search
   needs to be refined if the number is too large. The
   <object-search:item> element contains <object-search:domain> child
   elements defined in Section 3.1.

   Example of returning the list of object search items in an <info>
   response.

   S:<?xml version="1.0" encoding="UTF-8"?>
   S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
   S:   <response>
   S:      <result code="1000">
   S:         <msg>Command completed successfully</msg>
   S:      </result>
   S:      <resData>
   S:        <object-search:infData xmlns:object-search=
   S:          "urn:ietf:params:xml:ns:epp:object-search-0.1">
   S:          <object-search:list total="2">
   S:            <object-search:item>
   S:              <object-search:domain type="name" filter="begins">
   S:                example.com
   S:              </object-search:domain>
   S:            </object-search:item>
   S:            <object-search:item>
   S:              <object-search:domain type="name" filter="begins">
   S:                example.net
   S:              </object-search:domain>
   S:            </object-search:item>
   S:          </object-search:list>
   S:        </object-search:infData>
   S:      </resData>
   S:      <trID>
   S:         <clTRID>ABC-12345</clTRID>
   S:         <svTRID>54321-XYZ</svTRID>
   S:      </trID>
   S:   </response>
   S:</epp>

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4.1.1.2. Object Search Contacts

   A search for contact objects can be performed by using the <info>
   command with the <object-search> element and the
   <object-search:contact> child element, defined in Section 3.1.

   Example to search for a contact object in an <info> command.

   C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
   C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
   C:  <command>
   C:    <info>
   C:      <object-search:info xmlns:object-search=
   C:        "urn:ietf:params:xml:ns:epp:object-search-0.1">
   C:        <object-search:contact type="name" filter="contains">John
   C:        </object-search:contact>
   C:      </object-search:info>
   C:    </info>
   C:    <clTRID>ABC-12346</clTRID>
   C:  </command>
   C:</epp>

   When an <info> command has been processed successfully, the EPP
   <resData> element MUST contain a child <object-search:infData>
   element that identifies the object search namespace. The
   <object-search:infData> element contains the <object-search:list>
   element with zero or more <object-search:item> child elements. The
   "total" attribute is REQUIRED and MUST contain the total number of
   the search result. This allows the client to determine if the search
   needs to be refined if the number is too large. The
   <object-search:item> element contains the <object-search:contact>
   child element defined in Section 3.1.

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   Example of returning the list of object search items in an <info>
   response.
   
   S:<?xml version="1.0" encoding="UTF-8"?>
   S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
   S:   <response>
   S:      <result code="1000">
   S:         <msg>Command completed successfully</msg>
   S:      </result>
   S:      <resData>
   S:        <object-search:infData xmlns:object-search=
   S:          "urn:ietf:params:xml:ns:epp:object-search-0.1">
   S:          <object-search:list total="12345678">
   S:            <object-search:item>
   S:              <object-search:contact type="name" filter="contains">
   S:                sh8013
   S:              </object-search:contact>
   S:            </object-search:item>
   S:            <object-search:item>
   S:              <object-search:contact type="name" filter="contains">
   S:                sah8013
   S:              </object-search:contact>
   S:            </object-search:item>
   S:          </object-search:list>
   S:        </object-search:infData>
   S:      </resData>
   S:      <trID>
   S:         <clTRID>ABC-12346</clTRID>
   S:         <svTRID>54322-XYZ</svTRID>
   S:      </trID>
   S:   </response>
   S:</epp>
   
4.1.1.3 Object Search Hosts

   A search for host objects can be performed by using the <info>
   command with the <object-search> element and the
   <object-search:host> child element, defined in Section 3.1.

   Example to search for a host object in an <info> command.

   C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
   C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
   C:  <command>
   C:    <info>
   C:      <object-search:info xmlns:object-search=
   C:        "urn:ietf:params:xml:ns:epp:object-search-0.1">
   C:        <object-search:host type="name" filter="ends">example.com
   C:        </object-search:host>
   C:      </object-search:info>
   C:    </info>
   C:    <clTRID>ABC-12347</clTRID>
   C:  </command>
   C:</epp>

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   When an <info> command has been processed successfully, the EPP
   <resData> element MUST contain a child <object-search:infData>
   element that identifies the object search namespace. The
   <object-search:infData> element contains the <object-search:list>
   element with zero or more <object-search:item> child elements. The
   "total" attribute is REQUIRED and MUST contain the total number of
   the search result. This allows the client to determine if the search
   needs to be refined if the number is too large. The
   <object-search:item> element contains the <object-search:host> child
   element defined in Section 3.1.

   Example of returning the list of object search items in an <info>
   response.
   
   S:<?xml version="1.0" encoding="UTF-8"?>
   S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
   S:   <response>
   S:      <result code="1000">
   S:         <msg>Command completed successfully</msg>
   S:      </result>
   S:      <resData>
   S:        <object-search:infData xmlns:object-search=
   S:          "urn:ietf:params:xml:ns:epp:object-search-0.1">
   S:          <object-search:list total="34567">
   S:            <object-search:item>
   S:              <object-search:host type="name" filter="ends">
   S:                ns1.example.com
   S:              </object-search:host>
   S:            </object-search:item>
   S:            <object-search:item>
   S:              <object-search:host type="name" filter="ends">
   S:                ns2.example.com
   S:              </object-search:host>
   S:            </object-search:item>
   S:          </object-search:list>
   S:        </object-search:infData>
   S:      </resData>
   S:      <trID>
   S:         <clTRID>ABC-12347</clTRID>
   S:         <svTRID>54323-XYZ</svTRID>
   S:      </trID>
   S:   </response>
   S:</epp>

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4.2.  EPP Transform Commands

   EPP provides five commands to transform objects: <create> to create
   an instance of an object, <delete> to delete an instance of an
   object, <renew> to extend the validity period of an object,
   <transfer> to manage object sponsorship changes, and <update> to
   change information associated with an object.
   
   This extension does not add any elements to the EPP <create>,
   <delete>, <renew>, <transfer>, and <update>.

5.  Formal Syntax

   The EPP Object Search schema is presented here.
   
   The formal syntax presented here is a complete schema representation
   of the object mapping suitable for automated validation of EPP XML
   instances. The  <CODE BEGINS> and <CODE ENDS> tags are not part of
   the schema; they are used to note the beginning and end of the
   schema for URI registration purposes.

5.1.  Object Search EPP Mapping Schema

   <CODE BEGINS>
   <?xml version="1.0" encoding="UTF-8"?>
     <schema targetNamespace=
       "urn:ietf:params:xml:ns:epp:object-search-0.1"
       xmlns:eppcom="urn:ietf:params:xml:ns:eppcom-1.0"
       xmlns:epp="urn:ietf:params:xml:ns:epp-1.0"
       xmlns:object-search=
         "urn:ietf:params:xml:ns:epp:object-search-0.1"
       xmlns="https://www.w3.org/2001/XMLSchema"
       elementFormDefault="qualified">
     <!--
     Import common element types
     -->
     <import namespace="urn:ietf:params:xml:ns:eppcom-1.0"/>
     <import namespace="urn:ietf:params:xml:ns:epp-1.0"/>
     <annotation>
       <documentation>
         Extensible Provisioning Protocol v1.0
         Object Search Mapping Schema.
       </documentation>
     </annotation>
     <!--
      Info Response element
     -->
     <element name="infData" type="object-search:infDataType"/>
     <!--
      <info> response elements.
     -->
     <complexType name="infDataType">
       <sequence>

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         <element name="list" type="object-search:listDataType"/>
       </sequence>
     </complexType>
     <!--
      Attributes associated with the list info response
     -->
     <complexType name="listDataType">
       <choice>
         <element name="item" type="object-search:domainItemType"
          minOccurs="0" maxOccurs="unbounded"/>
         <element name="item" type="object-search:contactItemType"
          minOccurs="0" maxOccurs="unbounded"/>
         <element name="item" type="object-search:hostItemType"
          minOccurs="0" maxOccurs="unbounded"/>
       </choice>
     </complexType>
     <!--
      Attributes associated with the list item info response
     -->
     <complexType name="domainItemType">
       <sequence>
         <element name="type" type="object-search:domainTypeEnum"/>
         <element name="filter" type="object-search:filterEnum"/>
       </sequence>
     </complexType>
     <!--
      Attributes associated with the list item info response
     -->
     <complexType name="contactItemType">
       <sequence>
         <element name="type" type="object-search:contactTypeEnum"/>
         <element name="filter" type="object-search:filterEnum"/>
       </sequence>
     </complexType>
     <!--
      Attributes associated with the list item info response
     -->
     <complexType name="hostItemType">
       <sequence>
         <element name="type" type="object-search:hostTypeEnum"/>
         <element name="filter" type="object-search:filterEnum"/>
       </sequence>
     </complexType>
     <!--
      Enumerated list of domain types
     -->
     <simpleType name="domainTypeEnum">
       <restriction base="token">
         <enumeration value="name"/>
         <enumeration value="contact"/>
         <enumeration value="host"/>
         <enumeration value="status"/>

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         <enumeration value="crDate"/>
         <enumeration value="upDate"/>
         <enumeration value="exDate"/>
         <enumeration value="trDate"/>
       </restriction>
     </simpleType>
     <!--
      Enumerated list of contact types
     -->
     <simpleType name="contactTypeEnum">
       <restriction base="token">
         <enumeration value="id"/>
         <enumeration value="name"/>
         <enumeration value="orga"/>
         <enumeration value="street"/>
         <enumeration value="city"/>
         <enumeration value="state"/>
         <enumeration value="postcode"/>
         <enumeration value="email"/>
         <enumeration value="voice"/>
         <enumeration value="fax"/>
         <enumeration value="country"/>
       </restriction>
     </simpleType>
     <!--
      Enumerated list of host types
     -->
     <simpleType name="hostTypeEnum">
       <restriction base="token">
         <enumeration value="name"/>
         <enumeration value="ipv4"/>
         <enumeration value="ipv6"/>
       </restriction>
     </simpleType>
     <!--
      Enumerated list of filters
     -->
     <simpleType name="filterEnum">
       <restriction base="token">
         <enumeration value="exact"/>
         <enumeration value="begins"/>
         <enumeration value="ends"/>
         <enumeration value="contains"/>
       </restriction>
     </simpleType>
     <!--
      End of schema.
     -->
     </schema>
    <CODE ENDS>

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6.  IANA Considerations

6.1.  XML Namespace

   This document uses URNs to describe XML namespaces and XML schemas
   conforming to a registry mechanism defined in [RFC3688].

   Registration request for the object search namespace:
      URI: urn:ietf:params:xml:ns:epp:object-search-0.1
      Registrant Contact: IESG
      XML: None.  Namespace URIs do not represent an XML specification.

   Registration request for the object search schema:
      URI: urn:ietf:params:xml:schema:epp:object-search-0.1
      Registrant Contact: IESG
      XML: See the "Formal Syntax" section of this document.

6.2.  EPP Extension Registry

   The following registration of the EPP Extension Registry, described
   in [RFC7451], is requested:

   Name of Extension: Object Search for the Extensible Provisioning
   Protocol (EPP)
   Document status: Standards Track
   Reference: (insert the reference to RFC version of this document)
   Registrant Name and Email Address: IESG <iesg@ietf.org>
   TLDs: Any
   IPR Disclosure: None
   Status: Active
   Notes: None

7.  Security Considerations

   The mapping extensions described in this document do not provide any
   security services beyond those described by EPP [RFC5730] and
   protocol layers used by EPP.  The security considerations described
   in these other specifications apply to this specification as well.

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8.  Implementation Status

   Note to RFC Editor: Please remove this section and the reference to
   [RFC7942] before publication.

   This section records the status of known implementations of the
   protocol defined by this specification at the time of posting of this
   Internet-Draft, and is based on a proposal described in [RFC7942].
   The description of implementations in this section is intended to
   assist the IETF in its decision processes in progressing drafts to
   RFCs.  Please note that the listing of any individual implementation
   here does not imply endorsement by the IETF.  Furthermore, no effort
   has been spent to verify the information presented here that was
   supplied by IETF contributors.  This is not intended as, and must not
   be construed to be, a catalog of available implementations or their
   features.  Readers are advised to note that other implementations may
   exist.

   According to [RFC7942], "this will allow reviewers and working groups
   to assign due consideration to documents that have the benefit of
   running code, which may serve as evidence of valuable experimentation
   and feedback that have made the implemented protocols more mature. It
   is up to the individual working groups to use this information as
   they see fit".

9.  References

9.1.  Normative References

   [W3C.REC-xml11-20060816]
              Bray, T., Paoli, J., Sperberg-McQueen, M., Maler, E.,
              Yergeau, F., and J. Cowan, "Extensible Markup Language
              (XML) 1.1 (Second Edition)", World Wide Web Consortium
              Recommendation REC-xml11-20060816, 16 August 2006,
              <https://www.w3.org/TR/2006/REC-xml11-20060816>.
              
              Latest version available at
              <https://www.w3.org/TR/xml11/>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC5730]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
              STD 69, RFC 5730, DOI 10.17487/RFC5730, August 2009,
              <https://www.rfc-editor.org/info/rfc5730>.

   [RFC7942]  Sheffer, Y. and A. Farrel, "Improving Awareness of Running
              Code: The Implementation Status Section", BCP 205,
              RFC 7942, DOI 10.17487/RFC7942, July 2016,
              <https://www.rfc-editor.org/info/rfc7942>.

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   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

9.2.  Informative References

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [RFC7451]  Hollenbeck, S., "Extension Registry for the Extensible
              Provisioning Protocol", RFC 7451, DOI 10.17487/RFC7451,
              February 2015, <https://www.rfc-editor.org/info/rfc7451>.

Appendix A.  Change History

   TBD

Acknowledgments

   The author wish to thank the following persons for their feedback
   and suggestions: TBD
   
Authors' Addresses

   Tobias Sattler

   Email: mail@tobiassattler.com
   URI:   https://tobiassattler.com

   Jody Kolker
   GoDaddy Inc.
   2155 E GoDaddy Way
   Tempe, AZ  85284
   United States of America

   Email: jkolker@godaddy.com
   URI:   https://www.godaddy.com

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